inspector: add lengths for binary data descriptions

This CL adds support for ArrayBuffer and SharedArrayBuffer subtypes for injected
script source. It also adds the byteLength/size to the description of these
objects and for the upcoming "blob" subtype when appropriate.

This is dependent on a DevTools frontend patch to accept these new subtypes:
https://chromium-review.googlesource.com/c/582427/

Bug: chromium:653620
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
Change-Id: If8f612b54e82e6fd2f056545bd521868ba7349fd
Reviewed-on: https://chromium-review.googlesource.com/582233
Commit-Queue: Erik Luo <luoe@chromium.org>
Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46851}

src/inspector/injected-script-source.js

@@ -627,12 +627,18 @@ InjectedScript.prototype = {
             return className;
         }
 
-        if (subtype === "map" || subtype === "set") {
+        if (subtype === "map" || subtype === "set" || subtype === "blob") {
             if (typeof obj.size === "number")
                 return className + "(" + obj.size + ")";
             return className;
         }
 
+        if (subtype === "arraybuffer" || subtype === "dataview") {
+            if (typeof obj.byteLength === "number")
+                return className + "(" + obj.byteLength + ")";
+            return className;
+        }
+
         if (typeof obj === "function")
             return toString(obj);
 

src/inspector/v8-injected-script-host.cc

@@ -219,6 +219,14 @@ void V8InjectedScriptHost::subtypeCallback(
     info.GetReturnValue().Set(toV8StringInternalized(isolate, "promise"));
     return;
   }
+  if (value->IsArrayBuffer() || value->IsSharedArrayBuffer()) {
+    info.GetReturnValue().Set(toV8StringInternalized(isolate, "arraybuffer"));
+    return;
+  }
+  if (value->IsDataView()) {
+    info.GetReturnValue().Set(toV8StringInternalized(isolate, "dataview"));
+    return;
+  }
   std::unique_ptr<StringBuffer> subtype =
       unwrapInspector(info)->client()->valueSubtype(value);
   if (subtype) {

test/inspector/runtime/length-or-size-description-expected.txt

@@ -7,6 +7,12 @@ Array(0)
 Array(2)
 Uint8Array(0)
 Uint8Array(2)
+ArrayBuffer(0)
+ArrayBuffer(2)
+SharedArrayBuffer(0)
+SharedArrayBuffer(2)
+DataView(0)
+DataView(5)
 WeakMap
 WeakSet
 Set(0)
@@ -17,5 +23,11 @@ Array(0)
 Array(2)
 Uint8Array(0)
 Uint8Array(2)
+ArrayBuffer(0)
+ArrayBuffer(2)
+SharedArrayBuffer(0)
+SharedArrayBuffer(2)
+DataView(0)
+DataView(5)
 WeakMap
 WeakSet

test/inspector/runtime/length-or-size-description.js

@@ -2,7 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-let {session, contextGroup, Protocol} = InspectorTest.start("Test that descriptions for arrays, maps, and sets include the correct length or size.")
+// Flags: --harmony-sharedarraybuffer
+
+let {session, contextGroup, Protocol} = InspectorTest.start("Test that descriptions for arrays, maps, and sets include the correct length or size.");
 
 contextGroup.setupInjectedScriptEnvironment();
 
@@ -15,6 +17,12 @@ Promise.all([
   testExpression("new Array(2)"),
   testExpression("new Uint8Array()"),
   testExpression("new Uint8Array(2)"),
+  testExpression("new ArrayBuffer()"),
+  testExpression("new ArrayBuffer(2)"),
+  testExpression("new SharedArrayBuffer()"),
+  testExpression("new SharedArrayBuffer(2)"),
+  testExpression("new DataView(new ArrayBuffer())"),
+  testExpression("new DataView(new ArrayBuffer(5))"),
   // WeakMap and WeakSet should not have size in description.
   testExpression("new WeakMap([[{}, 42]])"),
   testExpression("new WeakSet([{}])")