Add tests for trace wrappers

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

Index: third_party/WebKit/Source/bindings/core/v8/ScriptWrappableVisitor.h
diff --git a/third_party/WebKit/Source/bindings/core/v8/ScriptWrappableVisitor.h b/third_party/WebKit/Source/bindings/core/v8/ScriptWrappableVisitor.h
index f350c602afbe49d27795d4d93ae659500e64be23..f075b5a9c9e257f0968b8ca5fb018d71a033b971 100644
--- a/third_party/WebKit/Source/bindings/core/v8/ScriptWrappableVisitor.h
+++ b/third_party/WebKit/Source/bindings/core/v8/ScriptWrappableVisitor.h
@@ -30,17 +30,17 @@ public:
         const void* object)
         : m_traceWrappersCallback(traceWrappersCallback)
         , m_heapObjectHeaderCallback(heapObjectHeaderCallback)
-        , m_object(object)
+        , m_rawObjectPointer(object)
     {
         DCHECK(m_traceWrappersCallback);
         DCHECK(m_heapObjectHeaderCallback);
-        DCHECK(m_object);
+        DCHECK(m_rawObjectPointer);
     }
 
     inline void traceWrappers(WrapperVisitor* visitor)
     {
-        if (m_object) {
-            m_traceWrappersCallback(visitor, m_object);
+        if (m_rawObjectPointer) {
+            m_traceWrappersCallback(visitor, m_rawObjectPointer);
         }
     }
 
@@ -50,29 +50,35 @@ public:
      */
     inline bool isWrapperHeaderMarked()
     {
-        return !m_object || heapObjectHeader()->isWrapperHeaderMarked();
+        return !m_rawObjectPointer || heapObjectHeader()->isWrapperHeaderMarked();
     }
 
+    /**
+     * Returns raw object pointer. Beware it doesn't necessarily point to the
+     * beginning of the object.
+     */
+    const void* rawObjectPointer() { return m_rawObjectPointer; }
+
 private:
     inline bool shouldBeInvalidated()
     {
-        return m_object && !heapObjectHeader()->isMarked();
+        return m_rawObjectPointer && !heapObjectHeader()->isMarked();
     }
 
     inline void invalidate()
     {
-        m_object = nullptr;
+        m_rawObjectPointer = nullptr;
     }
 
     inline const HeapObjectHeader* heapObjectHeader()
     {
-        DCHECK(m_object);
-        return m_heapObjectHeaderCallback(m_object);
+        DCHECK(m_rawObjectPointer);
+        return m_heapObjectHeaderCallback(m_rawObjectPointer);
     }
 
     void (*m_traceWrappersCallback)(const WrapperVisitor*, const void*);
     HeapObjectHeader* (*m_heapObjectHeaderCallback)(const void*);
-    const void* m_object;
+    const void* m_rawObjectPointer;
 };
 
 /**
@@ -151,6 +157,10 @@ public:
     void markWrappersInAllWorlds(const ScriptWrappable*) const override;
     void markWrappersInAllWorlds(const void*) const override {}
 
+    WTF::Deque<WrapperMarkingData>* getMarkingDeque() { return &m_markingDeque; }
+    WTF::Deque<WrapperMarkingData>* getVerifierDeque() { return &m_verifierDeque; }
+    WTF::Vector<HeapObjectHeader*>* getHeadersToUnmark() { return &m_headersToUnmark; }
+
 private:
     /**
      * Is wrapper tracing currently in progress? True if TracePrologue has been