Migrate HostZoomMap to live in StoragePartition.

chrome/browser/profiles/profile.h

Index: chrome/browser/profiles/profile.h
diff --git a/chrome/browser/profiles/profile.h b/chrome/browser/profiles/profile.h
index eb65083e6599c8c29d3cc10fa4817475c513fe59..1933d47ea31f4effc32a5eb51b23a2aa1373c7aa 100644
--- a/chrome/browser/profiles/profile.h
+++ b/chrome/browser/profiles/profile.h
@@ -15,6 +15,7 @@
 #include "components/domain_reliability/clear_mode.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/content_browser_client.h"
+#include "content/public/browser/host_zoom_map.h"
 
 class ChromeAppCacheService;
 class DevToolsNetworkController;
@@ -384,7 +385,19 @@ class Profile : public content::BrowserContext {
   // Creates an OffTheRecordProfile which points to this Profile.
   Profile* CreateOffTheRecordProfile();
 
+ protected:
+  // Allows a profile to track changes in zoom levels in another profile.
+  // This function, along with TrackZoomLevelChanged(), are placed in Profile
+  // to facilitate testing with TestingProfile.
+  void TrackZoomLevelsFromParent(Profile* parent);

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

nit: Name this TrackZoomLevelsFromParentForTest if it's only for testing.

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

This is also used to setup HostZoomMap tracking from the parent in non-test code
also.

+
  private:
+  // Callback function for tracking parent's zoom level changes.
+  void TrackZoomLevelChanged(
+      const content::HostZoomMap::ZoomLevelChange& change);
+
+  scoped_ptr<content::HostZoomMap::Subscription> track_zoom_subscription_;
+
   bool restored_last_session_;
 
   // Used to prevent the notification that this Profile is destroyed from