bindings: Adds check for attributes on prototype chains in CSSStyleDeclaration.

Source/bindings/core/v8/custom/V8CSSStyleDeclarationCustom.cpp

 /*
  * Copyright (C) 2007-2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 179 matching lines @@
     // NOTE: cssPropertyInfo lookups incur several mallocs.
     // Successful lookups have the same cost the first time, but are cached.
     if (cssPropertyInfo(v8Name.As<v8::String>(), info.GetIsolate())) {
         v8SetReturnValueInt(info, 0);
         return;
     }
 }
 
 void V8CSSStyleDeclaration::namedPropertyGetterCustom(v8::Local<v8::Name> name, const v8::PropertyCallbackInfo<v8::Value>& info)
 {
-    if (!name->IsString())
-        return;
-    // First look for API defined attributes on the style declaration object.
-    if (v8CallBoolean(info.Holder()->HasRealNamedCallbackProperty(info.GetIsolate()->GetCurrentContext(), name.As<v8::String>())))
-        return;
-
     // Search the style declaration.
     CSSPropertyInfo* propInfo = cssPropertyInfo(name.As<v8::String>(), info.GetIsolate());
 
     // Do not handle non-property names.
     if (!propInfo)
         return;
 
     CSSStyleDeclaration* impl = V8CSSStyleDeclaration::toImpl(info.Holder());
     RefPtrWillBeRawPtr<CSSValue> cssValue = impl->getPropertyCSSValueInternal(static_cast<CSSPropertyID>(propInfo->propID));
     if (cssValue) {
@@ skipping 18 matching lines @@
     ExceptionState exceptionState(ExceptionState::SetterContext, getPropertyName(static_cast<CSSPropertyID>(propInfo->propID)), "CSSStyleDeclaration", info.Holder(), info.GetIsolate());
     impl->setPropertyInternal(static_cast<CSSPropertyID>(propInfo->propID), propertyValue, false, exceptionState);
 
     if (exceptionState.throwIfNeeded())
         return;
 
     v8SetReturnValue(info, value);
 }
 
 } // namespace blink