Fix for crash when attaching a frame in WebUI renderer.

content/renderer/web_ui_extension.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/web_ui_extension.h"
 
 #include "base/memory/scoped_ptr.h"
 #include "base/values.h"
 #include "content/common/view_messages.h"
 #include "content/public/common/bindings_policy.h"
 #include "content/public/common/url_constants.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/public/renderer/render_view.h"
 #include "content/public/renderer/v8_value_converter.h"
+#include "content/renderer/chrome_object_extensions_utils.h"
 #include "content/renderer/web_ui_extension_data.h"
 #include "gin/arguments.h"
 #include "gin/function_template.h"
 #include "third_party/WebKit/public/web/WebDocument.h"
 #include "third_party/WebKit/public/web/WebKit.h"
 #include "third_party/WebKit/public/web/WebLocalFrame.h"
 #include "third_party/WebKit/public/web/WebView.h"
 #include "url/gurl.h"
 #include "v8/include/v8.h"
 
@@ skipping 37 matching lines @@
 //      a value was set by the browser. Else will return an empty string.
 void WebUIExtension::Install(blink::WebFrame* frame) {
   v8::Isolate* isolate = blink::mainThreadIsolate();
   v8::HandleScope handle_scope(isolate);
   v8::Handle<v8::Context> context = frame->mainWorldScriptContext();
   if (context.IsEmpty())
     return;
 
   v8::Context::Scope context_scope(context);
 
-  v8::Handle<v8::Object> global = context->Global();
-  v8::Handle<v8::Object> chrome =
-      global->Get(gin::StringToV8(isolate, "chrome"))->ToObject();
-  if (chrome.IsEmpty()) {
-    chrome = v8::Object::New(isolate);
-    global->Set(gin::StringToSymbol(isolate, "chrome"), chrome);
-  }
+  v8::Handle<v8::Object> chrome = GetOrCreateChromeObject(isolate,
+                                                          context->Global());
   chrome->Set(gin::StringToSymbol(isolate, "send"),
               gin::CreateFunctionTemplate(
                   isolate, base::Bind(&WebUIExtension::Send))->GetFunction());
   chrome->Set(gin::StringToSymbol(isolate, "getVariableValue"),
               gin::CreateFunctionTemplate(
                   isolate, base::Bind(&WebUIExtension::GetVariableValue))
                   ->GetFunction());
 }
 
 // static
@@ skipping 42 matching lines @@
 std::string WebUIExtension::GetVariableValue(const std::string& name) {
   blink::WebFrame* frame;
   RenderView* render_view;
   if (!ShouldRespondToRequest(&frame, &render_view))
     return std::string();
 
   return WebUIExtensionData::Get(render_view)->GetValue(name);
 }
 
 }  // namespace content