Fix crashes in AutomationInternalCustomBindings due to no v8 context.

chrome/renderer/extensions/automation_internal_custom_bindings.h

 // Copyright 2014 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.
 
 #ifndef CHROME_RENDERER_EXTENSIONS_AUTOMATION_INTERNAL_CUSTOM_BINDINGS_H_
 #define CHROME_RENDERER_EXTENSIONS_AUTOMATION_INTERNAL_CUSTOM_BINDINGS_H_
 
 #include "base/compiler_specific.h"
 #include "chrome/common/extensions/api/automation.h"
 #include "extensions/renderer/object_backed_native_handler.h"
@@ skipping 29 matching lines @@
 
   void OnMessageReceived(const IPC::Message& message);
 
   TreeCache* GetTreeCacheFromTreeID(int tree_id);
 
   ScriptContext* context() const {
     return ObjectBackedNativeHandler::context();
   }
 
  private:
+  // ObjectBackedNativeHandler overrides:
+  void Invalidate() override;
+
   // Returns whether this extension has the "interact" permission set (either
   // explicitly or implicitly after manifest parsing).
   void IsInteractPermitted(const v8::FunctionCallbackInfo<v8::Value>& args);
 
   // Returns an object with bindings that will be added to the
   // chrome.automation namespace.
   void GetSchemaAdditions(const v8::FunctionCallbackInfo<v8::Value>& args);
 
   // Get the routing ID for the extension.
   void GetRoutingID(const v8::FunctionCallbackInfo<v8::Value>& args);
@@ skipping 106 matching lines @@
   base::hash_map<ui::AXTree*, TreeCache*> axtree_to_tree_cache_map_;
   scoped_refptr<AutomationMessageFilter> message_filter_;
   bool is_active_profile_;
 
   DISALLOW_COPY_AND_ASSIGN(AutomationInternalCustomBindings);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_RENDERER_EXTENSIONS_AUTOMATION_INTERNAL_CUSTOM_BINDINGS_H_