Migrate HostZoomMap to live in StoragePartition.

content/public/browser/host_zoom_map.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_PUBLIC_BROWSER_HOST_ZOOM_MAP_H_
 #define CONTENT_PUBLIC_BROWSER_HOST_ZOOM_MAP_H_
 
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/callback_list.h"
 #include "content/common/content_export.h"
+#include "url/gurl.h"
 
 namespace content {
 
 class BrowserContext;
 class ResourceContext;
+class SiteInstance;
 class WebContents;
 
 // Maps hostnames to custom zoom levels.  Written on the UI thread and read on
 // any thread.  One instance per browser context. Must be created on the UI
 // thread, and it'll delete itself on the UI thread as well.
 // Zoom can be defined at three levels: default zoom, zoom for host, and zoom
 // for host with specific scheme. Setting any of the levels leaves settings
 // for other settings intact. Getting the zoom level starts at the most
 // specific setting and progresses to the less specific: first the zoom for the
 // host and scheme pair is checked, secondly the zoom for the host only and
 // lastly default zoom.
 
 class HostZoomMap {
  public:
   // Enum that indicates what was the scope of zoom level change.
   enum ZoomLevelChangeMode {
     ZOOM_CHANGED_FOR_HOST,            // Zoom level changed for host.
     ZOOM_CHANGED_FOR_SCHEME_AND_HOST, // Zoom level changed for scheme/host
                                       // pair.
     ZOOM_CHANGED_TEMPORARY_ZOOM,      // Temporary zoom change for specific
                                       // renderer, no scheme/host is specified.
+    ZOOM_CHANGED_DEFAULT_ZOOM_LEVEL,  // Notify when default level changes.
   };
 
   // Structure used to notify about zoom changes. Host and/or scheme are empty
   // if not applicable to |mode|.
   struct ZoomLevelChange {
     ZoomLevelChangeMode mode;
     std::string host;
     std::string scheme;
     double zoom_level;
   };
 
   typedef std::vector<ZoomLevelChange> ZoomLevelVector;
 
-  CONTENT_EXPORT static HostZoomMap* GetForBrowserContext(
+  CONTENT_EXPORT static HostZoomMap* GetDefaultForBrowserContext(
       BrowserContext* browser_context);
 
+  // Returns the HostZoomMap associated with this SiteInstance. The SiteInstance
+  // may serve multiple WebContents, and the HostZoomMap is the same for all of
+  // these WebContents.
+  CONTENT_EXPORT static HostZoomMap* Get(SiteInstance* instance);
+
+  // Returns the HostZoomMap associated with this WebContents. If multiple
+  // WebContents share the same SiteInstance, then they share a single
+  // HostZoomMap.
+  CONTENT_EXPORT static HostZoomMap* GetForWebContents(
+      const WebContents* contents);
+
   // Returns the current zoom level for the specified WebContents. May be
   // temporary or host-specific.
   CONTENT_EXPORT static double GetZoomLevel(const WebContents* web_contents);
 
   // Sets the current zoom level for the specified WebContents. The level may
   // be temporary or host-specific depending on the particular WebContents.
   CONTENT_EXPORT static void SetZoomLevel(const WebContents* web_contents,
                                           double level);
 
   // Copy the zoom levels from the given map. Can only be called on the UI
@@ skipping 71 matching lines @@
   virtual scoped_ptr<Subscription> AddZoomLevelChangedCallback(
       const ZoomLevelChangedCallback& callback) = 0;
 
  protected:
   virtual ~HostZoomMap() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_HOST_ZOOM_MAP_H_