Reland 73532.

chrome/browser/dom_ui/dom_ui.h

 // Copyright (c) 2010 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_BROWSER_DOM_UI_DOM_UI_H_
 #define CHROME_BROWSER_DOM_UI_DOM_UI_H_
 #pragma once
 
 #include <map>
 #include <string>
@@ skipping 87 matching lines @@
   // Returns the transition type that should be used for link clicks on this
   // Web UI. This will default to LINK but may be overridden.
   PageTransition::Type link_transition_type() const {
     return link_transition_type_;
   }
 
   int bindings() const {
     return bindings_;
   }
 
+  // Indicates whether RegisterMessageCallback() will overwrite an existing
+  // message callback mapping.  Serves as the hook for test mocks.
+  bool register_callback_overwrites() const {
+    return register_callback_overwrites_;
+  }
+
+  void register_callback_overwrites(bool value) {
+    register_callback_overwrites_ = value;
+  }
+
   // Call a Javascript function by sending its name and arguments down to
   // the renderer.  This is asynchronous; there's no way to get the result
   // of the call, and should be thought of more like sending a message to
   // the page.
   // There are variants for calls with more arguments.
   void CallJavascriptFunction(const std::wstring& function_name);
   void CallJavascriptFunction(const std::wstring& function_name,
                               const Value& arg);
   void CallJavascriptFunction(const std::wstring& function_name,
                               const Value& arg1,
@@ skipping 30 matching lines @@
   // Options that may be overridden by individual Web UI implementations. The
   // bool options default to false. See the public getters for more information.
   bool hide_favicon_;
   bool force_bookmark_bar_visible_;
   bool focus_location_bar_by_default_;
   bool should_hide_url_;
   string16 overridden_title_;  // Defaults to empty string.
   PageTransition::Type link_transition_type_;  // Defaults to LINK.
   int bindings_;  // The bindings from BindingsPolicy that should be enabled for
                   // this page.
+  bool register_callback_overwrites_;  // Defaults to false;
 
   // The DOMMessageHandlers we own.
   std::vector<DOMMessageHandler*> handlers_;
 
   // Non-owning pointer to the TabContents this DOMUI is associated with.
   TabContents* tab_contents_;
 
  private:
   // A map of message name -> message handling callback.
   typedef std::map<std::string, MessageCallback*> MessageCallbackMap;
@@ skipping 31 matching lines @@
   // Extract a string value from a list Value.
   std::wstring ExtractStringValue(const ListValue* value);
 
   DOMUI* dom_ui_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(DOMMessageHandler);
 };
 
 #endif  // CHROME_BROWSER_DOM_UI_DOM_UI_H_