Decouple TabLoader from SessionRestore.

chrome/browser/sessions/tab_loader.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_SESSIONS_TAB_LOADER_H_
 #define CHROME_BROWSER_SESSIONS_TAB_LOADER_H_
 
 #include <list>
 #include <set>
 
 #include "base/memory/memory_pressure_listener.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/timer/timer.h"
+#include "chrome/browser/sessions/session_restore_delegate.h"
 #include "chrome/browser/sessions/tab_loader_delegate.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
 namespace content {
 class NavigationController;
 class RenderWidgetHost;
 }
 
 // TabLoader is responsible for loading tabs after session restore has finished
 // creating all the tabs. Tabs are loaded after a previously tab finishes
 // loading or a timeout is reached. If the timeout is reached before a tab
 // finishes loading the timeout delay is doubled.
 //
 // TabLoader keeps a reference to itself when it's loading. When it has finished
 // loading, it drops the reference. If another profile is restored while the
 // TabLoader is loading, it will schedule its tabs to get loaded by the same
 // TabLoader. When doing the scheduling, it holds a reference to the TabLoader.
 //
 // This is not part of SessionRestoreImpl so that synchronous destruction
 // of SessionRestoreImpl doesn't have timing problems.
 class TabLoader : public content::NotificationObserver,
                   public base::RefCounted<TabLoader>,
+                  public SessionRestoreDelegate,
                   public TabLoaderCallback {
  public:
-  // Retrieves a pointer to the TabLoader instance shared between profiles, or
-  // creates a new TabLoader if it doesn't exist. If a TabLoader is created, its
-  // starting timestamp is set to |restore_started|.
-  static TabLoader* GetTabLoader(base::TimeTicks restore_started);
-
-  // Schedules a tab for loading.
-  void ScheduleLoad(content::NavigationController* controller);
-
-  // Notifies the loader that a tab has been scheduled for loading through
-  // some other mechanism.
-  void TabIsLoading(content::NavigationController* controller);
-
-  // Invokes |LoadNextTab| to load a tab.
-  //
-  // This must be invoked once to start loading.
-  void StartLoading();
+  // NotificationObserver method. Removes the specified tab and loads the next
+  // tab.
+  void Observe(int type,
+               const content::NotificationSource& source,
+               const content::NotificationDetails& details) override;
 
   // TabLoaderCallback:
   void SetTabLoadingEnabled(bool enable_tab_loading) override;
 
+  // Called to start restoring tabs.
+  static void RestoreTabs(const std::vector<RestoredTab>& tabs_,
+                          const base::TimeTicks& restore_started);
+
  private:
   friend class base::RefCounted<TabLoader>;
 
   typedef std::set<content::NavigationController*> TabsLoading;
   typedef std::list<content::NavigationController*> TabsToLoad;
   typedef std::set<content::RenderWidgetHost*> RenderWidgetHostSet;
 
   explicit TabLoader(base::TimeTicks restore_started);
   ~TabLoader() override;
 
+  // This is invoked once by RestoreTabs to start loading.
+  void StartLoading(const std::vector<RestoredTab>& tabs);
+
+  // Schedules a tab for loading.
+  void ScheduleLoad(content::NavigationController* controller);
+
+  // Notifies the loader that a tab has been scheduled for loading through
+  // some other mechanism.
+  void TabIsLoading(content::NavigationController* controller);
+
   // Loads the next tab. If there are no more tabs to load this deletes itself,
   // otherwise |force_load_timer_| is restarted.
   void LoadNextTab();
 
   // Starts a timer to load load the next tab once expired before the current
   // tab loading is finished.
   void StartTimer();
 
-  // NotificationObserver method. Removes the specified tab and loads the next
-  // tab.
-  void Observe(int type,
-               const content::NotificationSource& source,
-               const content::NotificationDetails& details) override;
-
   // Removes the listeners from the specified tab and removes the tab from
   // the set of tabs to load and list of tabs we're waiting to get a load
   // from.
   void RemoveTab(content::NavigationController* tab);
 
   // Invoked from |force_load_timer_|. Doubles |force_load_delay_multiplier_|
   // and invokes |LoadNextTab| to load the next tab
   void ForceLoadTimerFired();
 
   // Returns the RenderWidgetHost associated with a tab if there is one,
@@ skipping 61 matching lines @@
   // For keeping TabLoader alive while it's loading even if no
   // SessionRestoreImpls reference it.
   scoped_refptr<TabLoader> this_retainer_;
 
   static TabLoader* shared_tab_loader_;
 
   DISALLOW_COPY_AND_ASSIGN(TabLoader);
 };
 
 #endif  // CHROME_BROWSER_SESSIONS_TAB_LOADER_H_