Introduce infrastructure for tracing ScriptWrappables.

third_party/WebKit/Source/bindings/core/v8/ScriptWrappable.cpp

Index: third_party/WebKit/Source/bindings/core/v8/ScriptWrappable.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/ScriptWrappable.cpp b/third_party/WebKit/Source/bindings/core/v8/ScriptWrappable.cpp
index 3534a4ebfb5d2b1cd83854203e91f08945483b90..7c1d7a4e05102f475634b18fbe4c4068799bc8f5 100644
--- a/third_party/WebKit/Source/bindings/core/v8/ScriptWrappable.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/ScriptWrappable.cpp
@@ -5,6 +5,7 @@
 #include "bindings/core/v8/ScriptWrappable.h"
 
 #include "bindings/core/v8/DOMDataStore.h"
+#include "bindings/core/v8/ScriptWrappableHeapTracer.h"
 #include "bindings/core/v8/V8DOMWrapper.h"
 
 namespace blink {
@@ -35,4 +36,9 @@ v8::Local<v8::Object> ScriptWrappable::associateWithWrapper(v8::Isolate* isolate
     return V8DOMWrapper::associateObjectWithWrapper(isolate, this, wrapperTypeInfo, wrapper);
 }
 
+void ScriptWrappable::markWrapper(v8::Isolate* isolate) const

[haraken, 2016/04/18 04:35:41]

This method looks redundant. The caller sites of this method should just call
ScriptWrappableHeapTracer::markWrapper.

(Below I'm suggesting renaming it to
ScriptWrappableHeapTracer::markWrappersInAllWorlds.)

[Marcel Hlopko, 2016/04/18 11:45:35]

I agree, in this form the method is useless. I changed it so it actually marks
its wrapper, if contains one. See the comment above for longer discussion.

+{
+    ScriptWrappableHeapTracer::markWrapper(this, isolate);
+}
+
 } // namespace blink