Apply all blink changes between @202695 and tip of trunk

Source/bindings/core/dart/DartJsInteropData.h

Index: Source/bindings/core/dart/DartJsInteropData.h
diff --git a/Source/bindings/core/dart/DartJsInteropData.h b/Source/bindings/core/dart/DartJsInteropData.h
index 9eb72ba253b597c00d815884a6275ff6d4d411af..8a493f6cba494f1447b9334717409c1385f83569 100644
--- a/Source/bindings/core/dart/DartJsInteropData.h
+++ b/Source/bindings/core/dart/DartJsInteropData.h
@@ -44,6 +44,7 @@ public:
     v8::Local<v8::Function> captureThisFunction();
     v8::Local<v8::Function> wrapDartFunction();
     v8::Local<v8::Function> instanceofFunction();
+    v8::Local<v8::String> existingDartWrapperHiddenField(v8::Isolate*);
 
     bool jsObjectImplDefined() { return m_jsObjectImplDefined; }
     void setJsObjectImplDefined() { m_jsObjectImplDefined = true; }
@@ -55,6 +56,8 @@ private:
     v8::Persistent<v8::Function> m_wrapDartFunction;
     v8::Persistent<v8::Function> m_instanceofFunction;
 
+    v8::Persistent<v8::String> m_existingDartWrapperHiddenField;
+
     bool m_jsObjectImplDefined;
 
     // FIXME: add maps of Dart to V8 and V8 to Dart objects.