Migrate HostZoomMap to live in StoragePartition.

chrome/browser/ui/webui/options/content_settings_handler.cc

 // 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.
 
 #include "chrome/browser/ui/webui/options/content_settings_handler.h"
 
 #include <algorithm>
 #include <map>
 #include <vector>
 
@@ skipping 497 matching lines @@
   pref_change_registrar_.Add(
       prefs::kVideoCaptureAllowed,
       base::Bind(&ContentSettingsHandler::UpdateMediaSettingsView,
                  base::Unretained(this)));
   pref_change_registrar_.Add(
       prefs::kEnableDRM,
       base::Bind(
           &ContentSettingsHandler::UpdateProtectedContentExceptionsButton,
           base::Unretained(this)));
 
-  content::HostZoomMap* host_zoom_map =
-      content::HostZoomMap::GetForBrowserContext(context);
+  // Here we only subscribe to the HostZoomMap for the default storage partition
+  // and we're only interested in non-temporary, host-only zoom levels.

[awong, 2014/08/12 21:07:06]

Needs more "why" in the comment. :)

[wjmaclean, 2014/08/13 17:16:03]

Done.

   host_zoom_map_subscription_ =
-      host_zoom_map->AddZoomLevelChangedCallback(
-          base::Bind(&ContentSettingsHandler::OnZoomLevelChanged,
-                     base::Unretained(this)));
+      content::HostZoomMap::GetForBrowserContext(context)
+          ->AddZoomLevelChangedCallback(
+              base::Bind(&ContentSettingsHandler::OnZoomLevelChanged,
+                         base::Unretained(this)));
 
   flash_settings_manager_.reset(new PepperFlashSettingsManager(this, context));
 }
 
 void ContentSettingsHandler::InitializePage() {
   media_settings_ = MediaSettingsInfo();
   RefreshFlashMediaSettings();
 
   UpdateHandlersEnabledRadios();
   UpdateAllExceptionsViewsFromModel();
@@ skipping 1040 matching lines @@
 void ContentSettingsHandler::UpdateProtectedContentExceptionsButton() {
   PrefService* prefs = user_prefs::UserPrefs::Get(GetBrowserContext(web_ui()));
   // Exceptions apply only when the feature is enabled.
   bool enable_exceptions = prefs->GetBoolean(prefs::kEnableDRM);
   web_ui()->CallJavascriptFunction(
       "ContentSettings.enableProtectedContentExceptions",
       base::FundamentalValue(enable_exceptions));
 }
 
 }  // namespace options