Implement V8InspectorSession::initializeCommandLineAPIScope

In https://crrev.com/c/2842128, a concern was raised that using
`V8InspectorSession::createCommandLineAPI` directly would not cache the command line
API definitions and V8 could expose a higher level API for this use
case. This CL exposes `InjectedScript::ContextScope` via V8InspectorSession.
If this approach is approved, V8InspectorSession::createCommandLineAPI
could be removed.

Example usage: https://crrev.com/c/2858964

Bug: chromium:1200705
Change-Id: Ib9fcadcb9bbd75c08f0122b0e4ee61e2874c4f8a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2857640
Commit-Queue: Alex Rudenko <alexrudenko@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74289}

include/v8-inspector.h

@@ -152,6 +152,10 @@ class V8_EXPORT V8InspectorSession {
     virtual v8::Local<v8::Value> get(v8::Local<v8::Context>) = 0;
     virtual ~Inspectable() = default;
   };
+  class V8_EXPORT CommandLineAPIScope {
+   public:
+    virtual ~CommandLineAPIScope() = default;
+  };
   virtual void addInspectedObject(std::unique_ptr<Inspectable>) = 0;
 
   // Dispatching protocol messages.
@@ -163,6 +167,8 @@ class V8_EXPORT V8InspectorSession {
 
   virtual v8::Local<v8::Object> createCommandLineAPI(
       v8::Local<v8::Context> context) = 0;
+  virtual std::unique_ptr<V8InspectorSession::CommandLineAPIScope>
+  initializeCommandLineAPIScope(int executionContextId) = 0;
 
   // Debugger actions.
   virtual void schedulePauseOnNextStatement(StringView breakReason,

src/inspector/injected-script.h

@@ -173,7 +173,8 @@ class InjectedScript final {
     int m_sessionId;
   };
 
-  class ContextScope : public Scope {
+  class ContextScope : public Scope,
+                       public V8InspectorSession::CommandLineAPIScope {
    public:
     ContextScope(V8InspectorSessionImpl*, int executionContextId);
     ~ContextScope() override;

src/inspector/v8-inspector-session-impl.cc

@@ -155,6 +155,20 @@ V8InspectorSessionImpl::~V8InspectorSessionImpl() {
   m_inspector->disconnect(this);
 }
 
+std::unique_ptr<V8InspectorSession::CommandLineAPIScope>
+V8InspectorSessionImpl::initializeCommandLineAPIScope(int executionContextId) {
+  auto scope =
+      std::make_unique<InjectedScript::ContextScope>(this, executionContextId);
+  auto result = scope->initialize();
+  if (!result.IsSuccess()) {
+    return nullptr;
+  }
+
+  scope->installCommandLineAPI();
+
+  return scope;
+}
+
 v8::Local<v8::Object> V8InspectorSessionImpl::createCommandLineAPI(
     v8::Local<v8::Context> context) {
   return inspector()->console()->createCommandLineAPI(context, sessionId());

src/inspector/v8-inspector-session-impl.h

@@ -53,6 +53,9 @@ class V8InspectorSessionImpl : public V8InspectorSession,
   v8::Local<v8::Object> createCommandLineAPI(
       v8::Local<v8::Context> context) override;
 
+  std::unique_ptr<V8InspectorSession::CommandLineAPIScope>
+  initializeCommandLineAPIScope(int executionContextId) override;
+
   Response findInjectedScript(int contextId, InjectedScript*&);
   Response findInjectedScript(RemoteObjectIdBase*, InjectedScript*&);
   void reset();