Migrate HostZoomMap to live in StoragePartition.

chrome/browser/ui/zoom/zoom_controller.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_UI_ZOOM_ZOOM_CONTROLLER_H_
 #define CHROME_BROWSER_UI_ZOOM_ZOOM_CONTROLLER_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 55 matching lines @@
     bool can_show_bubble;
   };
 
   ~ZoomController() override;
 
   ZoomMode zoom_mode() const { return zoom_mode_; }
 
   // Convenience method to get default zoom level. Implemented here for
   // inlining.
   double GetDefaultZoomLevel() const {
-    // TODO(wjmaclean) Make this refer to the webcontents-specific HostZoomMap
-    // when that becomes available.
-    return content::HostZoomMap::GetDefaultForBrowserContext(browser_context_)->
-        GetDefaultZoomLevel();
+    return content::HostZoomMap::GetForWebContents(web_contents())
+        ->GetDefaultZoomLevel();
   }
 
   // Convenience method to quickly check if the tab's at default zoom.
   bool IsAtDefaultZoom() const;
 
   // Returns which image should be loaded for the current zoom level.
   int GetResourceForZoomLevel() const;
 
   const extensions::Extension* last_extension() const {
     return last_extension_.get();
@@ skipping 71 matching lines @@
   ObserverList<ZoomObserver> observers_;
 
   content::BrowserContext* browser_context_;
 
   scoped_ptr<content::HostZoomMap::Subscription> zoom_subscription_;
 
   DISALLOW_COPY_AND_ASSIGN(ZoomController);
 };
 
 #endif  // CHROME_BROWSER_UI_ZOOM_ZOOM_CONTROLLER_H_