[wrapper-tracing] Support for incrementally tracing ScopedPersistent

third_party/WebKit/Source/bindings/core/v8/ScriptWrappableVisitorVerifier.h

Index: third_party/WebKit/Source/bindings/core/v8/ScriptWrappableVisitorVerifier.h
diff --git a/third_party/WebKit/Source/bindings/core/v8/ScriptWrappableVisitorVerifier.h b/third_party/WebKit/Source/bindings/core/v8/ScriptWrappableVisitorVerifier.h
index 98acaf2f0155a4cb97649c2b82167b7738de7402..956293bea81954131edfa8f001bab39fb60c4f63 100644
--- a/third_party/WebKit/Source/bindings/core/v8/ScriptWrappableVisitorVerifier.h
+++ b/third_party/WebKit/Source/bindings/core/v8/ScriptWrappableVisitorVerifier.h
@@ -33,27 +33,25 @@ class ScriptWrappableVisitorVerifier : public WrapperVisitor {
 #undef DECLARE_DISPATCH_TRACE_WRAPPERS
   void dispatchTraceWrappers(const void*) const override {}
 
-  void traceWrappers(const ScopedPersistent<v8::Value>*) const override {}
-  void traceWrappers(const ScopedPersistent<v8::Object>*) const override {}
-  void markWrapper(const v8::PersistentBase<v8::Object>*) const override {}
+  void traceWrappers(const TraceWrapperV8Reference<v8::Value>&) const override {
+  }
+  void markWrapper(const v8::PersistentBase<v8::Value>*) const override {}
 
   void pushToMarkingDeque(
       void (*traceWrappersCallback)(const WrapperVisitor*, const void*),
       HeapObjectHeader* (*heapObjectHeaderCallback)(const void*),
       const void* object) const override {
     if (!heapObjectHeaderCallback(object)->isWrapperHeaderMarked()) {
-      /*
-             * If this branch is hit, it means that a white (not discovered by
-             * traceWrappers) object was assigned as a member to a black object
-             * (already processed by traceWrappers). Black object will not be
-             * processed anymore so White object will remain undetected and
-             * therefore its wrapper and all wrappers reachable from it would be
-             * collected.
-             *
-             * Most often this means there is a write barrier missing somewhere.
-             * Check backtrace to see which classes are causing this and review
-             * all the places where white class is set to the black class.
-             */
+      // If this branch is hit, it means that a white (not discovered by
+      // traceWrappers) object was assigned as a member to a black object
+      // (already processed by traceWrappers). Black object will not be
+      // processed anymore so White object will remain undetected and
+      // therefore its wrapper and all wrappers reachable from it would be
+      // collected.
+
+      // Most often this means there is a write barrier missing somewhere.
+      // Check backtrace to see which classes are causing this and review all
+      // the places where white class is set to the black class.
       NOTREACHED();
     }
     traceWrappersCallback(this, object);