bindings,devtools: Shows DOM attributes' values in DevTools.

Source/bindings/core/v8/V8DOMWrapper.cpp

 /*
  * Copyright (C) 2009 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 75 matching lines @@
 {
     if (value.IsEmpty() || !value->IsObject())
         return false;
     v8::Local<v8::Object> object = v8::Local<v8::Object>::Cast(value);
 
     if (object->InternalFieldCount() < v8DefaultWrapperInternalFieldCount)
         return false;
 
     const WrapperTypeInfo* untrustedWrapperTypeInfo = toWrapperTypeInfo(object);
     V8PerIsolateData* perIsolateData = V8PerIsolateData::from(isolate);
+    if (!(untrustedWrapperTypeInfo && perIsolateData))
+        return false;
     return perIsolateData->hasInstance(untrustedWrapperTypeInfo, object);
 }
 
 bool V8DOMWrapper::hasInternalFieldsSet(v8::Local<v8::Value> value)
 {
     if (value.IsEmpty() || !value->IsObject())
         return false;
     v8::Local<v8::Object> object = v8::Local<v8::Object>::Cast(value);
 
     if (object->InternalFieldCount() < v8DefaultWrapperInternalFieldCount)
         return false;
 
     const ScriptWrappable* untrustedScriptWrappable = toScriptWrappable(object);
     const WrapperTypeInfo* untrustedWrapperTypeInfo = toWrapperTypeInfo(object);
     return untrustedScriptWrappable
         && untrustedWrapperTypeInfo
         && untrustedWrapperTypeInfo->ginEmbedder == gin::kEmbedderBlink;
 }
 
 } // namespace blink