Roll third_party/inspector_protocol to cf45a6e89b17cdc9eeacdef4c003fcc55f7ec2a0

This roll includes one change: "[inspector_protocol] support fall through and moveable Maybe" [1].

[1] https://codereview.chromium.org/2468923002/

BUG=none
R=dgozman@chromium.org

Review-Url: https://codereview.chromium.org/2469063002
Cr-Commit-Position: refs/heads/master@{#40687}

test/inspector/debugger/set-breakpoint-before-enabling-expected.txt

 setBreakpointByUrl error: undefined
 setBreakpoint error: {
   "code": -32602,
-  "message": "Invalid request",
+  "message": "Invalid parameters",
   "data": "location: object expected"
 }
-

third_party/inspector_protocol/CodeGenerator.py

@@ -329,6 +329,11 @@ def resolve_type(protocol, prop):
     return protocol.type_definitions[prop["type"]]
 
 
+def new_style(domain):
+    domains = []
+    return domain["domain"] in domains
+
+
 def join_arrays(dict, keys):
     result = []
     for key in keys:
@@ -339,7 +344,7 @@ def join_arrays(dict, keys):
 
 def has_disable(commands):
     for command in commands:
-        if command["name"] == "disable":
+        if command["name"] == "disable" and (not ("handlers" in command) or "renderer" in command["handlers"]):
             return True
     return False
 
@@ -421,6 +426,7 @@ def main():
             "type_definition": functools.partial(type_definition, protocol),
             "has_disable": has_disable,
             "format_include": format_include,
+            "new_style": new_style,
         }
 
         if domain["domain"] in protocol.generate_domains:
@@ -448,7 +454,6 @@ def main():
             "ValueConversions_h.template",
             "Maybe_h.template",
             "Array_h.template",
-            "BackendCallback_h.template",
             "DispatcherBase_h.template",
             "Parser_h.template",
         ]

third_party/inspector_protocol/README.v8

@@ -2,7 +2,7 @@ Name: inspector protocol
 Short Name: inspector_protocol
 URL: https://chromium.googlesource.com/deps/inspector_protocol/
 Version: 0
-Revision: 6c15061ecf7168e520d33633b217e029e74760a7
+Revision: cf45a6e89b17cdc9eeacdef4c003fcc55f7ec2a0
 License: BSD
 License File: LICENSE
 Security Critical: no

third_party/inspector_protocol/inspector_protocol.gni

@@ -33,7 +33,6 @@ template("inspector_protocol_generate") {
       invoker.config_file,
       "$inspector_protocol_dir/lib/Allocator_h.template",
       "$inspector_protocol_dir/lib/Array_h.template",
-      "$inspector_protocol_dir/lib/BackendCallback_h.template",
       "$inspector_protocol_dir/lib/Collections_h.template",
       "$inspector_protocol_dir/lib/DispatcherBase_cpp.template",
       "$inspector_protocol_dir/lib/DispatcherBase_h.template",

third_party/inspector_protocol/inspector_protocol.gypi

@@ -7,7 +7,6 @@
     'inspector_protocol_files': [
       'lib/Allocator_h.template',
       'lib/Array_h.template',
-      'lib/BackendCallback_h.template',
       'lib/Collections_h.template',
       'lib/DispatcherBase_cpp.template',
       'lib/DispatcherBase_h.template',

third_party/inspector_protocol/lib/BackendCallback_h.template

-// Copyright (c) 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef {{"_".join(config.protocol.namespace)}}_BackendCallback_h
-#define {{"_".join(config.protocol.namespace)}}_BackendCallback_h
-
-//#include "Forward.h"
-
-{% for namespace in config.protocol.namespace %}
-namespace {{namespace}} {
-{% endfor %}
-
-class {{config.lib.export_macro}} BackendCallback {
-public:
-    virtual ~BackendCallback() { }
-    virtual void sendFailure(const ErrorString&) = 0;
-};
-
-{% for namespace in config.protocol.namespace %}
-} // namespace {{namespace}}
-{% endfor %}
-
-#endif // !defined({{"_".join(config.protocol.namespace)}}_BackendCallback_h)

third_party/inspector_protocol/lib/DispatcherBase_cpp.template

@@ -10,7 +10,45 @@ namespace {{namespace}} {
 {% endfor %}
 
 // static
-const char DispatcherBase::kInvalidRequest[] = "Invalid request";
+DispatchResponse DispatchResponse::OK()
+{
+    DispatchResponse result;
+    result.m_status = kSuccess;
+    result.m_errorCode = kParseError;
+    return result;
+}
+
+// static
+DispatchResponse DispatchResponse::Error(const String& error)
+{
+    DispatchResponse result;
+    result.m_status = kError;
+    result.m_errorCode = kServerError;
+    result.m_errorMessage = error;
+    return result;
+}
+
+// static
+DispatchResponse DispatchResponse::InternalError()
+{
+    DispatchResponse result;
+    result.m_status = kError;
+    result.m_errorCode = kInternalError;
+    result.m_errorMessage = "Internal error";
+    return result;
+}
+
+// static
+DispatchResponse DispatchResponse::FallThrough()
+{
+    DispatchResponse result;
+    result.m_status = kFallThrough;
+    result.m_errorCode = kParseError;
+    return result;
+}
+
+// static
+const char DispatcherBase::kInvalidParamsString[] = "Invalid parameters";
 
 DispatcherBase::WeakPtr::WeakPtr(DispatcherBase* dispatcher) : m_dispatcher(dispatcher) { }
 
@@ -31,11 +69,11 @@ void DispatcherBase::Callback::dispose()
     m_backendImpl = nullptr;
 }
 
-void DispatcherBase::Callback::sendIfActive(std::unique_ptr<protocol::DictionaryValue> partialMessage, const ErrorString& invocationError)
+void DispatcherBase::Callback::sendIfActive(std::unique_ptr<protocol::DictionaryValue> partialMessage, const DispatchResponse& response)
 {
     if (!m_backendImpl || !m_backendImpl->get())
         return;
-    m_backendImpl->get()->sendResponse(m_callId, invocationError, nullptr, std::move(partialMessage));
+    m_backendImpl->get()->sendResponse(m_callId, response, std::move(partialMessage));
     m_backendImpl = nullptr;
 }
 
@@ -64,10 +102,10 @@ bool DispatcherBase::getCommandName(const String& message, String* result)
     return true;
 }
 
-void DispatcherBase::sendResponse(int callId, const ErrorString& invocationError, ErrorSupport* errors, std::unique_ptr<protocol::DictionaryValue> result)
+void DispatcherBase::sendResponse(int callId, const DispatchResponse& response, std::unique_ptr<protocol::DictionaryValue> result)
 {
-    if (invocationError.length() || (errors && errors->hasErrors())) {
-        reportProtocolError(callId, ServerError, invocationError, errors);
+    if (response.status() == DispatchResponse::kError) {
+        reportProtocolError(callId, response.errorCode(), response.errorMessage(), nullptr);
         return;
     }
 
@@ -78,24 +116,18 @@ void DispatcherBase::sendResponse(int callId, const ErrorString& invocationError
         m_frontendChannel->sendProtocolResponse(callId, responseMessage->toJSONString());
 }
 
-void DispatcherBase::sendResponse(int callId, const ErrorString& invocationError, std::unique_ptr<protocol::DictionaryValue> result)
+void DispatcherBase::sendResponse(int callId, const DispatchResponse& response)
 {
-    sendResponse(callId, invocationError, nullptr, std::move(result));
+    sendResponse(callId, response, DictionaryValue::create());
 }
 
-void DispatcherBase::sendResponse(int callId, const ErrorString& invocationError)
-{
-    sendResponse(callId, invocationError, nullptr, DictionaryValue::create());
-}
-
-static void reportProtocolErrorTo(FrontendChannel* frontendChannel, int callId, DispatcherBase::CommonErrorCode code, const String& errorMessage, ErrorSupport* errors)
+static void reportProtocolErrorTo(FrontendChannel* frontendChannel, int callId, DispatchResponse::ErrorCode code, const String& errorMessage, ErrorSupport* errors)
 {
     if (!frontendChannel)
         return;
     std::unique_ptr<protocol::DictionaryValue> error = DictionaryValue::create();
     error->setInteger("code", code);
     error->setString("message", errorMessage);
-    DCHECK(error);
     if (errors && errors->hasErrors())
         error->setString("data", errors->errors());
     std::unique_ptr<protocol::DictionaryValue> message = DictionaryValue::create();
@@ -104,7 +136,19 @@ static void reportProtocolErrorTo(FrontendChannel* frontendChannel, int callId,
     frontendChannel->sendProtocolResponse(callId, message->toJSONString());
 }
 
-void DispatcherBase::reportProtocolError(int callId, CommonErrorCode code, const String& errorMessage, ErrorSupport* errors)
+static void reportProtocolErrorTo(FrontendChannel* frontendChannel, DispatchResponse::ErrorCode code, const String& errorMessage)
+{
+    if (!frontendChannel)
+        return;
+    std::unique_ptr<protocol::DictionaryValue> error = DictionaryValue::create();
+    error->setInteger("code", code);
+    error->setString("message", errorMessage);
+    std::unique_ptr<protocol::DictionaryValue> message = DictionaryValue::create();
+    message->setObject("error", std::move(error));
+    frontendChannel->sendProtocolNotification(message->toJSONString());
+}
+
+void DispatcherBase::reportProtocolError(int callId, DispatchResponse::ErrorCode code, const String& errorMessage, ErrorSupport* errors)
 {
     reportProtocolErrorTo(m_frontendChannel, callId, code, errorMessage, errors);
 }
@@ -132,38 +176,46 @@ void UberDispatcher::registerBackend(const String& name, std::unique_ptr<protoco
     m_dispatchers[name] = std::move(dispatcher);
 }
 
-void UberDispatcher::dispatch(std::unique_ptr<Value> parsedMessage)
+DispatchResponse::Status UberDispatcher::dispatch(std::unique_ptr<Value> parsedMessage)
 {
-    if (!parsedMessage)
-        return;
+    if (!parsedMessage) {
+        reportProtocolErrorTo(m_frontendChannel, DispatchResponse::kParseError, "Message must be a valid JSON");
+        return DispatchResponse::kError;
+    }
     std::unique_ptr<protocol::DictionaryValue> messageObject = DictionaryValue::cast(std::move(parsedMessage));
-    if (!messageObject)
-        return;
+    if (!messageObject) {
+        reportProtocolErrorTo(m_frontendChannel, DispatchResponse::kInvalidRequest, "Message must be an object");
+        return DispatchResponse::kError;
+    }
 
     int callId = 0;
     protocol::Value* callIdValue = messageObject->get("id");
     bool success = callIdValue && callIdValue->asInteger(&callId);
-    if (!success)
-        return;
+    if (!success) {
+        reportProtocolErrorTo(m_frontendChannel, DispatchResponse::kInvalidRequest, "Message must have integer 'id' porperty");
+        return DispatchResponse::kError;
+    }
 
     protocol::Value* methodValue = messageObject->get("method");
     String method;
     success = methodValue && methodValue->asString(&method);
-    if (!success)
-        return;
+    if (!success) {
+        reportProtocolErrorTo(m_frontendChannel, callId, DispatchResponse::kInvalidRequest, "Message must have string 'method' porperty", nullptr);
+        return DispatchResponse::kError;
+    }
 
     size_t dotIndex = method.find(".");
     if (dotIndex == StringUtil::kNotFound) {
-        reportProtocolErrorTo(m_frontendChannel, callId, DispatcherBase::MethodNotFound, "'" + method + "' wasn't found", nullptr);
-        return;
+        reportProtocolErrorTo(m_frontendChannel, callId, DispatchResponse::kMethodNotFound, "'" + method + "' wasn't found", nullptr);
+        return DispatchResponse::kError;
     }
     String domain = StringUtil::substring(method, 0, dotIndex);
     auto it = m_dispatchers.find(domain);
     if (it == m_dispatchers.end()) {
-        reportProtocolErrorTo(m_frontendChannel, callId, DispatcherBase::MethodNotFound, "'" + method + "' wasn't found", nullptr);
-        return;
+        reportProtocolErrorTo(m_frontendChannel, callId, DispatchResponse::kMethodNotFound, "'" + method + "' wasn't found", nullptr);
+        return DispatchResponse::kError;
     }
-    it->second->dispatch(callId, method, std::move(messageObject));
+    return it->second->dispatch(callId, method, std::move(messageObject));
 }
 
 UberDispatcher::~UberDispatcher() = default;

third_party/inspector_protocol/lib/DispatcherBase_h.template

@@ -5,7 +5,6 @@
 #ifndef {{"_".join(config.protocol.namespace)}}_DispatcherBase_h
 #define {{"_".join(config.protocol.namespace)}}_DispatcherBase_h
 
-//#include "BackendCallback.h"
 //#include "Collections.h"
 //#include "ErrorSupport.h"
 //#include "Forward.h"
@@ -17,10 +16,44 @@ namespace {{namespace}} {
 
 class WeakPtr;
 
+class {{config.lib.export_macro}} DispatchResponse {
+public:
+    enum Status {
+        kSuccess = 0,
+        kError = 1,
+        kFallThrough = 2,
+        kAsync = 3
+    };
+
+    enum ErrorCode {
+        kParseError = -32700,
+        kInvalidRequest = -32600,
+        kMethodNotFound = -32601,
+        kInvalidParams = -32602,
+        kInternalError = -32603,
+        kServerError = -32000,
+    };
+
+    Status status() const { return m_status; }
+    const String& errorMessage() const { return m_errorMessage; }
+    ErrorCode errorCode() const { return m_errorCode; }
+    bool isSuccess() const { return m_status == kSuccess; }
+
+    static DispatchResponse OK();
+    static DispatchResponse Error(const String&);
+    static DispatchResponse InternalError();
+    static DispatchResponse FallThrough();
+
+private:
+    Status m_status;
+    String m_errorMessage;
+    ErrorCode m_errorCode;
+};
+
 class {{config.lib.export_macro}} DispatcherBase {
     PROTOCOL_DISALLOW_COPY(DispatcherBase);
 public:
-    static const char kInvalidRequest[];
+    static const char kInvalidParamsString[];
     class {{config.lib.export_macro}} WeakPtr {
     public:
         explicit WeakPtr(DispatcherBase*);
@@ -32,14 +65,14 @@ public:
         DispatcherBase* m_dispatcher;
     };
 
-    class {{config.lib.export_macro}} Callback : public protocol::BackendCallback {
+    class {{config.lib.export_macro}} Callback {
     public:
         Callback(std::unique_ptr<WeakPtr> backendImpl, int callId);
         virtual ~Callback();
         void dispose();
 
     protected:
-        void sendIfActive(std::unique_ptr<protocol::DictionaryValue> partialMessage, const ErrorString& invocationError);
+        void sendIfActive(std::unique_ptr<protocol::DictionaryValue> partialMessage, const DispatchResponse& response);
 
     private:
         std::unique_ptr<WeakPtr> m_backendImpl;
@@ -49,24 +82,14 @@ public:
     explicit DispatcherBase(FrontendChannel*);
     virtual ~DispatcherBase();
 
-    enum CommonErrorCode {
-        ParseError = -32700,
-        InvalidRequest = -32600,
-        MethodNotFound = -32601,
-        InvalidParams = -32602,
-        InternalError = -32603,
-        ServerError = -32000,
-    };
-
     static bool getCommandName(const String& message, String* result);
 
-    virtual void dispatch(int callId, const String& method, std::unique_ptr<protocol::DictionaryValue> messageObject) = 0;
+    virtual DispatchResponse::Status dispatch(int callId, const String& method, std::unique_ptr<protocol::DictionaryValue> messageObject) = 0;
 
-    void sendResponse(int callId, const ErrorString&, ErrorSupport*, std::unique_ptr<protocol::DictionaryValue> result);
-    void sendResponse(int callId, const ErrorString&, std::unique_ptr<protocol::DictionaryValue> result);
-    void sendResponse(int callId, const ErrorString&);
+    void sendResponse(int callId, const DispatchResponse&, std::unique_ptr<protocol::DictionaryValue> result);
+    void sendResponse(int callId, const DispatchResponse&);
 
-    void reportProtocolError(int callId, CommonErrorCode, const String& errorMessage, ErrorSupport* errors);
+    void reportProtocolError(int callId, DispatchResponse::ErrorCode, const String& errorMessage, ErrorSupport* errors);
     void clearFrontend();
 
     std::unique_ptr<WeakPtr> weakPtr();
@@ -81,7 +104,7 @@ class {{config.lib.export_macro}} UberDispatcher {
 public:
     explicit UberDispatcher(FrontendChannel*);
     void registerBackend(const String& name, std::unique_ptr<protocol::DispatcherBase>);
-    void dispatch(std::unique_ptr<Value> message);
+    DispatchResponse::Status dispatch(std::unique_ptr<Value> message);
     FrontendChannel* channel() { return m_frontendChannel; }
     virtual ~UberDispatcher();
 

third_party/inspector_protocol/lib/Forward_h.template

@@ -19,12 +19,14 @@ namespace {{namespace}} {
 
 template<typename T> class Array;
 class DictionaryValue;
+class DispatchResponse;
 using ErrorString = String;
 class ErrorSupport;
 class FundamentalValue;
 class ListValue;
 template<typename T> class Maybe;
 class Object;
+using Response = DispatchResponse;
 class SerializedValue;
 class StringValue;
 class UberDispatcher;

third_party/inspector_protocol/lib/Maybe_h.template

@@ -16,6 +16,7 @@ class Maybe {
 public:
     Maybe() : m_value() { }
     Maybe(std::unique_ptr<T> value) : m_value(std::move(value)) { }
+    Maybe(Maybe&& other) : m_value(std::move(other.m_value)) { }
     void operator=(std::unique_ptr<T> value) { m_value = std::move(value); }
     T* fromJust() const { DCHECK(m_value); return m_value.get(); }
     T* fromMaybe(T* defaultValue) const { return m_value ? m_value.get() : defaultValue; }
@@ -30,6 +31,7 @@ class MaybeBase {
 public:
     MaybeBase() : m_isJust(false) { }
     MaybeBase(T value) : m_isJust(true), m_value(value) { }
+    MaybeBase(MaybeBase&& other) : m_isJust(other.m_isJust), m_value(std::move(other.m_value)) { }
     void operator=(T value) { m_value = value; m_isJust = true; }
     T fromJust() const { DCHECK(m_isJust); return m_value; }
     T fromMaybe(const T& defaultValue) const { return m_isJust ? m_value : defaultValue; }
@@ -46,6 +48,7 @@ class Maybe<bool> : public MaybeBase<bool> {
 public:
     Maybe() { }
     Maybe(bool value) : MaybeBase(value) { }
+    Maybe(Maybe&& other) : MaybeBase(std::move(other)) { }
     using MaybeBase::operator=;
 };
 
@@ -54,6 +57,7 @@ class Maybe<int> : public MaybeBase<int> {
 public:
     Maybe() { }
     Maybe(int value) : MaybeBase(value) { }
+    Maybe(Maybe&& other) : MaybeBase(std::move(other)) { }
     using MaybeBase::operator=;
 };
 
@@ -62,6 +66,7 @@ class Maybe<double> : public MaybeBase<double> {
 public:
     Maybe() { }
     Maybe(double value) : MaybeBase(value) { }
+    Maybe(Maybe&& other) : MaybeBase(std::move(other)) { }
     using MaybeBase::operator=;
 };
 
@@ -70,6 +75,7 @@ class Maybe<String> : public MaybeBase<String> {
 public:
     Maybe() { }
     Maybe(const String& value) : MaybeBase(value) { }
+    Maybe(Maybe&& other) : MaybeBase(std::move(other)) { }
     using MaybeBase::operator=;
 };
 

third_party/inspector_protocol/templates/TypeBuilder_cpp.template

@@ -150,7 +150,11 @@ const char* {{ literal | to_title_case}} = "{{literal}}";
 void Frontend::{{event.name}}(
     {%- for parameter in event.parameters %}
       {% if "optional" in parameter -%}
+        {%- if new_style(domain) -%}
+        Maybe<{{resolve_type(parameter).raw_type}}>
+        {%- else -%}
         const Maybe<{{resolve_type(parameter).raw_type}}>&
+        {%- endif -%}
       {%- else -%}
         {{resolve_type(parameter).pass_type}}
       {%- endif %} {{parameter.name}}{%- if not loop.last -%}, {% endif -%}
@@ -192,32 +196,32 @@ public:
   {% endfor %}
     }
     ~DispatcherImpl() override { }
-    void dispatch(int callId, const String& method, std::unique_ptr<protocol::DictionaryValue> messageObject) override;
+    DispatchResponse::Status dispatch(int callId, const String& method, std::unique_ptr<protocol::DictionaryValue> messageObject) override;
 
 protected:
-    using CallHandler = void (DispatcherImpl::*)(int callId, std::unique_ptr<DictionaryValue> messageObject, ErrorSupport* errors);
+    using CallHandler = DispatchResponse::Status (DispatcherImpl::*)(int callId, std::unique_ptr<DictionaryValue> messageObject, ErrorSupport* errors);
     using DispatchMap = protocol::HashMap<String, CallHandler>;
     DispatchMap m_dispatchMap;
 
   {% for command in domain.commands %}
     {% if "redirect" in command %}{% continue %}{% endif %}
     {% if "handlers" in command and not ("renderer" in command["handlers"]) %}{% continue %}{% endif %}
-    void {{command.name}}(int callId, std::unique_ptr<DictionaryValue> requestMessageObject, ErrorSupport*);
+    DispatchResponse::Status {{command.name}}(int callId, std::unique_ptr<DictionaryValue> requestMessageObject, ErrorSupport*);
   {% endfor %}
 
     Backend* m_backend;
 };
 
-void DispatcherImpl::dispatch(int callId, const String& method, std::unique_ptr<protocol::DictionaryValue> messageObject)
+DispatchResponse::Status DispatcherImpl::dispatch(int callId, const String& method, std::unique_ptr<protocol::DictionaryValue> messageObject)
 {
     protocol::HashMap<String, CallHandler>::iterator it = m_dispatchMap.find(method);
     if (it == m_dispatchMap.end()) {
-        reportProtocolError(callId, MethodNotFound, "'" + method + "' wasn't found", nullptr);
-        return;
+        reportProtocolError(callId, DispatchResponse::kMethodNotFound, "'" + method + "' wasn't found", nullptr);
+        return DispatchResponse::kError;
     }
 
     protocol::ErrorSupport errors;
-    (this->*(it->second))(callId, std::move(messageObject), &errors);
+    return (this->*(it->second))(callId, std::move(messageObject), &errors);
 }
 
   {% for command in domain.commands %}
@@ -233,7 +237,11 @@ public:
     void sendSuccess(
       {%- for parameter in command.returns -%}
         {%- if "optional" in parameter -%}
+          {%- if new_style(domain) -%}
+        Maybe<{{resolve_type(parameter).raw_type}}> {{parameter.name}}
+          {%- else -%}
         const Maybe<{{resolve_type(parameter).raw_type}}>& {{parameter.name}}
+          {%- endif -%}
         {%- else -%}
         {{resolve_type(parameter).pass_type}} {{parameter.name}}
         {%- endif -%}
@@ -249,19 +257,26 @@ public:
         resultObject->setValue("{{parameter.name}}", ValueConversions<{{resolve_type(parameter).raw_type}}>::serialize({{resolve_type(parameter).to_raw_type % parameter.name}}));
             {% endif %}
           {% endfor %}
-        sendIfActive(std::move(resultObject), ErrorString());
+        sendIfActive(std::move(resultObject), DispatchResponse::OK());
     }
 
+      {% if new_style(domain) %}
+    void sendFailure(const DispatchResponse& response) override
+    {
+        DCHECK(response.status() == DispatchResponse::kError);
+        sendIfActive(nullptr, response);
+    }
+      {% else %}
     void sendFailure(const ErrorString& error) override
     {
         DCHECK(error.length());
-        sendIfActive(nullptr, error);
+        sendIfActive(nullptr, DispatchResponse::Error(error));
     }
-
+      {% endif %}
 };
     {% endif %}
 
-void DispatcherImpl::{{command.name}}(int callId, std::unique_ptr<DictionaryValue> requestMessageObject, ErrorSupport* errors)
+DispatchResponse::Status DispatcherImpl::{{command.name}}(int callId, std::unique_ptr<DictionaryValue> requestMessageObject, ErrorSupport* errors)
 {
     {% if "parameters" in command %}
     // Prepare input parameters.
@@ -282,15 +297,12 @@ void DispatcherImpl::{{command.name}}(int callId, std::unique_ptr<DictionaryValu
       {% endfor %}
     errors->pop();
     if (errors->hasErrors()) {
-        reportProtocolError(callId, InvalidParams, kInvalidRequest, errors);
-        return;
+        reportProtocolError(callId, DispatchResponse::kInvalidParams, kInvalidParamsString, errors);
+        return DispatchResponse::kError;
     }
     {% endif %}
-    {% if "async" in command %}
-    std::unique_ptr<{{command.name | to_title_case}}CallbackImpl> callback(new {{command.name | to_title_case}}CallbackImpl(weakPtr(), callId));
-    {% elif "returns" in command %}
+    {% if "returns" in command and not ("async" in command) %}
     // Declare output parameters.
-    std::unique_ptr<protocol::DictionaryValue> result = DictionaryValue::create();
       {% for property in command.returns %}
         {% if "optional" in property %}
     Maybe<{{resolve_type(property).raw_type}}> out_{{property.name}};
@@ -300,24 +312,40 @@ void DispatcherImpl::{{command.name}}(int callId, std::unique_ptr<DictionaryValu
       {% endfor %}
     {% endif %}
 
-    std::unique_ptr<DispatcherBase::WeakPtr> weak = weakPtr();
     {% if not("async" in command) %}
+    std::unique_ptr<DispatcherBase::WeakPtr> weak = weakPtr();
+      {% if not new_style(domain) %}
     ErrorString error;
     m_backend->{{command.name}}(&error
+      {%- else %}
+    DispatchResponse response = m_backend->{{command.name}}(
+      {%- endif -%}
       {%- for property in command.parameters -%}
+        {%- if not loop.first or not new_style(domain) -%}, {% endif -%}
         {%- if "optional" in property -%}
-        , in_{{property.name}}
+          {%- if new_style(domain) -%}
+        std::move(in_{{property.name}})
           {%- else -%}
-        , {{resolve_type(property).to_pass_type % ("in_" + property.name)}}
+        in_{{property.name}}
+          {%- endif -%}
+        {%- else -%}
+        {{resolve_type(property).to_pass_type % ("in_" + property.name)}}
         {%- endif -%}
       {%- endfor %}
       {%- if "returns" in command %}
         {%- for property in command.returns -%}
-          , &out_{{property.name}}
+          {%- if not loop.first or command.parameters or not new_style(domain) -%}, {% endif -%}
+          &out_{{property.name}}
         {%- endfor %}
       {% endif %});
-      {% if "returns" in command and not("async" in command) %}
-    if (!error.length()) {
+      {% if not new_style(domain) %}
+    DispatchResponse response = error.length() ? DispatchResponse::Error(error) : DispatchResponse::OK();
+      {% endif %}
+      {% if "returns" in command %}
+    if (response.status() == DispatchResponse::kFallThrough)
+        return response.status();
+    std::unique_ptr<protocol::DictionaryValue> result = DictionaryValue::create();
+    if (response.status() == DispatchResponse::kSuccess) {
         {% for parameter in command.returns %}
           {% if "optional" in parameter %}
         if (out_{{parameter.name}}.isJust())
@@ -328,21 +356,30 @@ void DispatcherImpl::{{command.name}}(int callId, std::unique_ptr<DictionaryValu
         {% endfor %}
     }
     if (weak->get())
-        weak->get()->sendResponse(callId, error, std::move(result));
+        weak->get()->sendResponse(callId, response, std::move(result));
       {% else %}
     if (weak->get())
-        weak->get()->sendResponse(callId, error);
+        weak->get()->sendResponse(callId, response);
       {% endif %}
-    {%- else %}
+    return response.status();
+    {% else %}
+    std::unique_ptr<{{command.name | to_title_case}}CallbackImpl> callback(new {{command.name | to_title_case}}CallbackImpl(weakPtr(), callId));
     m_backend->{{command.name}}(
       {%- for property in command.parameters -%}
+        {%- if not loop.first -%}, {% endif -%}
         {%- if "optional" in property -%}
-        in_{{property.name}},
+          {%- if new_style(domain) -%}
+        std::move(in_{{property.name}})
+          {%- else -%}
+        in_{{property.name}}
+          {%- endif -%}
         {%- else -%}
-        {{resolve_type(property).to_pass_type % ("in_" + property.name)}},
+        {{resolve_type(property).to_pass_type % ("in_" + property.name)}}
         {%- endif -%}
       {%- endfor -%}
+        {%- if command.parameters -%}, {% endif -%}
         std::move(callback));
+    return DispatchResponse::kAsync;
     {% endif %}
 }
   {% endfor %}

third_party/inspector_protocol/templates/TypeBuilder_h.template

@@ -191,28 +191,45 @@ public:
     {% if "redirect" in command %}{% continue %}{% endif %}
     {% if ("handlers" in command) and not ("renderer" in command["handlers"]) %}{% continue %}{% endif %}
     {% if "async" in command %}
-    class {{config.protocol.export_macro}} {{command.name | to_title_case}}Callback : public BackendCallback {
+    class {{config.protocol.export_macro}} {{command.name | to_title_case}}Callback {
     public:
         virtual void sendSuccess(
       {%- for parameter in command.returns -%}
         {%- if "optional" in parameter -%}
+          {%- if new_style(domain) -%}
+            Maybe<{{resolve_type(parameter).raw_type}}> {{parameter.name}}
+          {%- else -%}
             const Maybe<{{resolve_type(parameter).raw_type}}>& {{parameter.name}}
+          {%- endif -%}
         {%- else -%}
                 {{resolve_type(parameter).pass_type}} {{parameter.name}}
         {%- endif -%}
         {%- if not loop.last -%}, {% endif -%}
       {%- endfor -%}
         ) = 0;
+      {% if new_style(domain) %}
+        virtual void sendFailure(const DispatchResponse&) = 0;
+      {% else %}
+        virtual void sendFailure(const ErrorString&) = 0;
+      {% endif %}
     };
     {% endif %}
+    {%- if not("async" in command) and new_style(domain) %}
+    virtual DispatchResponse {{command.name}}(
+    {%- else %}
     virtual void {{command.name}}(
-    {%- if not("async" in command) -%}
+    {%- endif %}
+    {%- if not("async" in command) and not new_style(domain) -%}
         ErrorString*
     {%- endif -%}
     {%- for parameter in command.parameters -%}
-        {%- if (not loop.first) or not("async" in command) -%}, {% endif -%}
+      {%- if (not loop.first) or (not ("async" in command) and not new_style(domain)) -%}, {% endif -%}
       {%- if "optional" in parameter -%}
+        {%- if new_style(domain) -%}
+        Maybe<{{resolve_type(parameter).raw_type}}> in_{{parameter.name}}
+        {%- else -%}
         const Maybe<{{resolve_type(parameter).raw_type}}>& in_{{parameter.name}}
+        {%- endif -%}
       {%- else -%}
         {{resolve_type(parameter).pass_type}} in_{{parameter.name}}
       {%- endif -%}
@@ -222,10 +239,11 @@ public:
         std::unique_ptr<{{command.name | to_title_case}}Callback> callback
     {%- else -%}
       {%- for parameter in command.returns -%}
+        {%- if (not loop.first) or command.parameters or not new_style(domain) -%}, {% endif -%}
         {%- if "optional" in parameter -%}
-        , Maybe<{{resolve_type(parameter).raw_type}}>* out_{{parameter.name}}
+        Maybe<{{resolve_type(parameter).raw_type}}>* out_{{parameter.name}}
         {%- else -%}
-        , {{resolve_type(parameter).type}}* out_{{parameter.name}}
+        {{resolve_type(parameter).type}}* out_{{parameter.name}}
         {%- endif -%}
       {%- endfor -%}
     {%- endif -%}
@@ -233,8 +251,26 @@ public:
   {% endfor %}
 
   {% if not has_disable(domain.commands) %}
+    {% if new_style(domain) %}
+    virtual DispatchResponse disable()
+    {
+        return DispatchResponse::OK();
+    }
+    {% else %}
     virtual void disable(ErrorString*) { }
     {% endif %}
+  {% endif %}
+
+    // TODO(dgozman): remove once all domains migrated.
+    static void disableMe(Backend* backend)
+    {
+  {% if new_style(domain) %}
+        backend->disable();
+  {% else %}
+        ErrorString error;
+        backend->disable(&error);
+  {% endif %}
+    }
 };
 
 // ------------- Frontend interface.
@@ -247,7 +283,11 @@ public:
     void {{event.name}}(
     {%- for parameter in event.parameters -%}
       {%- if "optional" in parameter -%}
+        {%- if new_style(domain) -%}
+        Maybe<{{resolve_type(parameter).raw_type}}> {{parameter.name}} = Maybe<{{resolve_type(parameter).raw_type}}>()
+        {%- else -%}
         const Maybe<{{resolve_type(parameter).raw_type}}>& {{parameter.name}} = Maybe<{{resolve_type(parameter).raw_type}}>()
+        {%- endif -%}
       {%- else -%}
         {{resolve_type(parameter).pass_type}} {{parameter.name}}
       {%- endif -%}{%- if not loop.last -%}, {% endif -%}