Add setting to isolate zoom changes by default.

chrome/browser/ui/zoom/chrome_zoom_level_otr_delegate.h

Index: chrome/browser/ui/zoom/chrome_zoom_level_otr_delegate.h
diff --git a/chrome/browser/ui/zoom/chrome_zoom_level_otr_delegate.h b/chrome/browser/ui/zoom/chrome_zoom_level_otr_delegate.h
index 5ea6ff8f800bb02007dccadb90564d30fb9f38c2..84738963de63e33266941d8b90515f0bbe751d33 100644
--- a/chrome/browser/ui/zoom/chrome_zoom_level_otr_delegate.h
+++ b/chrome/browser/ui/zoom/chrome_zoom_level_otr_delegate.h
@@ -5,11 +5,15 @@
 #ifndef CHROME_BROWSER_UI_ZOOM_CHROME_ZOOM_LEVEL_OTR_DELEGATE_H_
 #define CHROME_BROWSER_UI_ZOOM_CHROME_ZOOM_LEVEL_OTR_DELEGATE_H_
 
+#include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
+#include "chrome/browser/ui/zoom/chrome_zoom_prefs_helper.h"
+#include "components/prefs/pref_change_registrar.h"
+#include "components/prefs/pref_service.h"
+#include "components/zoom/zoom_prefs_delegate.h"
 #include "content/public/browser/host_zoom_map.h"
-#include "content/public/browser/zoom_level_delegate.h"
 
 namespace zoom {
 class ZoomEventManager;
@@ -17,25 +21,38 @@ class ZoomEventManager;
 
 // This class is a light-weight version of ChromeZoomLevelPrefs and is used
 // to connect an OTR StoragePartition's HostZoomMap to the OTR profile's
-// ZoomEventManager.
-class ChromeZoomLevelOTRDelegate : public content::ZoomLevelDelegate {
+// ZoomEventManager and to provide the parent profile's default zoom scope.
+class ChromeZoomLevelOTRDelegate : public zoom::ZoomPrefsDelegate {
  public:
   ChromeZoomLevelOTRDelegate(
+      PrefService* pref_service,
+      const base::FilePath& profile_path,
+      const base::FilePath& partition_path,
       base::WeakPtr<zoom::ZoomEventManager> zoom_event_manager);
   ~ChromeZoomLevelOTRDelegate() override;
 
-  // content::ZoomLevelDelegate
+  // zoom::ZoomPrefsDelegate
   void InitHostZoomMap(content::HostZoomMap* host_zoom_map) override;
 
+  bool GetZoomScopeIsPerOriginPref() const override;
+  std::unique_ptr<DefaultZoomScopeSubscription>
+  RegisterDefaultZoomScopeCallback(const base::Closure& callback) override;
+
  private:
   // This is a callback function that receives notifications from HostZoomMap
   // when per-host zoom levels change. It is used to update the per-host
   // zoom levels (if any) managed by this class (for its associated partition).
   void OnZoomLevelChanged(const content::HostZoomMap::ZoomLevelChange& change);
 
+  void OnParentScopeChanged();
+
+  ChromeZoomPrefsHelper partitioned_prefs_;
   base::WeakPtr<zoom::ZoomEventManager> zoom_event_manager_;
   content::HostZoomMap* host_zoom_map_;
   std::unique_ptr<content::HostZoomMap::Subscription> zoom_subscription_;
+  base::CallbackList<void(void)> default_scope_changed_callbacks_;
+  bool last_scope_was_per_origin_;
+  PrefChangeRegistrar pref_registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeZoomLevelOTRDelegate);
 };