Simplify ZoomController by removing DefaultZoomLevel prefs machinery.

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 52 matching lines @@
     double old_zoom_level;
     double new_zoom_level;
     ZoomController::ZoomMode zoom_mode;
     bool can_show_bubble;
   };
 
   virtual ~ZoomController();
 
   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();
+  }
+
   // 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 52 matching lines @@
 
   // True if changes to zoom level can trigger the zoom notification bubble.
   bool can_show_bubble_;
 
   // The current zoom mode.
   ZoomMode zoom_mode_;
 
   // Current zoom level.
   double zoom_level_;
 
-  // Used to access the default zoom level preference.
-  DoublePrefMember default_zoom_level_;
-
   scoped_ptr<ZoomChangedEventData> event_data_;
 
   // Keeps track of the extension (if any) that initiated the last zoom change
   // that took effect.
   scoped_refptr<const extensions::Extension> last_extension_;
 
   // Observer receiving notifications on state changes.
   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_