WebUI: Add JavaScript lifecycle-control to WebUIMessageHandler.

content/browser/webui/web_ui_impl.h

 // Copyright (c) 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.
 
 #ifndef CONTENT_BROWSER_WEBUI_WEB_UI_IMPL_H_
 #define CONTENT_BROWSER_WEBUI_WEB_UI_IMPL_H_
 
 #include <map>
 #include <memory>
 #include <set>
@@ skipping 37 matching lines @@
   int GetBindings() const override;
   void SetBindings(int bindings) override;
   bool HasRenderFrame() override;
   void AddMessageHandler(WebUIMessageHandler* handler) override;
   typedef base::Callback<void(const base::ListValue*)> MessageCallback;
   void RegisterMessageCallback(const std::string& message,
                                const MessageCallback& callback) override;
   void ProcessWebUIMessage(const GURL& source_url,
                            const std::string& message,
                            const base::ListValue& args) override;
+  bool CanCallJavascript() override;
   void CallJavascriptFunction(const std::string& function_name) override;
   void CallJavascriptFunction(const std::string& function_name,
                               const base::Value& arg) override;
   void CallJavascriptFunction(const std::string& function_name,
                               const base::Value& arg1,
                               const base::Value& arg2) override;
   void CallJavascriptFunction(const std::string& function_name,
                               const base::Value& arg1,
                               const base::Value& arg2,
                               const base::Value& arg3) override;
@@ skipping 50 matching lines @@
   const std::string frame_name_;
 
   std::unique_ptr<WebUIController> controller_;
 
   DISALLOW_COPY_AND_ASSIGN(WebUIImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_WEBUI_WEB_UI_IMPL_H_