[Sync] Componentize synced_tab_delegate

chrome/browser/sync/sessions/page_revisit_broadcaster.h

 // Copyright 2015 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_SYNC_SESSIONS_PAGE_REVISIT_BROADCASTER_H_
 #define CHROME_BROWSER_SYNC_SESSIONS_PAGE_REVISIT_BROADCASTER_H_
 
 #include "base/memory/scoped_vector.h"
 #include "components/sync_sessions/revisit/page_visit_observer.h"
 #include "ui/base/page_transition_types.h"
 #include "url/gurl.h"
 
 namespace bookmarks {
 class BookmarkModel;
 }  // namespace bookmarks
 
 namespace history {
 class HistoryService;
 }  // namespace history
 
+namespace sync_sessions {
+class SyncSessionsClient;
+}
+
 namespace browser_sync {
 
 class SessionsSyncManager;
 
 // This class has the job of creating and holding onto the PageVisitObservers
 // that are to be notified on page change for purposes of instrumenting
 // revisists.
 class PageRevisitBroadcaster {
  public:
   PageRevisitBroadcaster(SessionsSyncManager* sessions,
+                         sync_sessions::SyncSessionsClient* sessions_client,
                          history::HistoryService* history,
                          bookmarks::BookmarkModel* bookmarks);
   ~PageRevisitBroadcaster();
 
   // Broadcasts to all observers the given page visit event. Should only be
   // called when the url changes.
   void OnPageVisit(const GURL& url, const ui::PageTransition transition);
 
  private:
   friend class PageRevisitBroadcasterTest;
 
   // We convert between enums here for a couple reasons. We don't want to force
   // observers to depend on ui/, and the high bit masks don't work for emitting
   // histograms. Some of the high bit masks correspond to cases we're
   // particularly interested in and want to treat as first class values.
   static sync_sessions::PageVisitObserver::TransitionType ConvertTransitionEnum(
       const ui::PageTransition original);
 
+  // The client of this sync sessions datatype.
+  sync_sessions::SyncSessionsClient* const sessions_client_;
+
   ScopedVector<sync_sessions::PageVisitObserver> revisit_observers_;
 
   DISALLOW_COPY_AND_ASSIGN(PageRevisitBroadcaster);
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_SESSIONS_PAGE_REVISIT_BROADCASTER_H_