[DevTools] Issue zoom from DevToolsWindow instead of browser commands.

chrome/browser/devtools/devtools_window.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 CHROME_BROWSER_DEVTOOLS_DEVTOOLS_WINDOW_H_
 #define CHROME_BROWSER_DEVTOOLS_DEVTOOLS_WINDOW_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 308 matching lines @@
   virtual void AddFileSystem() OVERRIDE;
   virtual void RemoveFileSystem(const std::string& file_system_path) OVERRIDE;
   virtual void UpgradeDraggedFileSystemPermissions(
       const std::string& file_system_url) OVERRIDE;
   virtual void IndexPath(int request_id,
                          const std::string& file_system_path) OVERRIDE;
   virtual void StopIndexing(int request_id) OVERRIDE;
   virtual void SearchInPath(int request_id,
                             const std::string& file_system_path,
                             const std::string& query) OVERRIDE;
+  virtual void ZoomIn() OVERRIDE;
+  virtual void ZoomOut() OVERRIDE;
+  virtual void ResetZoom() OVERRIDE;
 
   // DevToolsFileHelper callbacks.
   void FileSavedAs(const std::string& url);
   void CanceledFileSaveAs(const std::string& url);
   void AppendedTo(const std::string& url);
   void FileSystemsLoaded(
       const std::vector<DevToolsFileHelper::FileSystem>& file_systems);
   void FileSystemAdded(const DevToolsFileHelper::FileSystem& file_system);
   void IndexingTotalWorkCalculated(int request_id,
                                    const std::string& file_system_path,
@@ skipping 54 matching lines @@
   bool intercepted_page_beforeunload_;
   base::Closure load_completed_callback_;
 
   scoped_ptr<DevToolsEmbedderMessageDispatcher> embedder_message_dispatcher_;
   base::WeakPtrFactory<DevToolsWindow> weak_factory_;
   base::TimeTicks inspect_element_start_time_;
   DISALLOW_COPY_AND_ASSIGN(DevToolsWindow);
 };
 
 #endif  // CHROME_BROWSER_DEVTOOLS_DEVTOOLS_WINDOW_H_