Merge of 97624 to 835 branch.

content/browser/tab_contents/tab_contents.h

 // Copyright (c) 2011 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 CONTENT_BROWSER_TAB_CONTENTS_TAB_CONTENTS_H_
 #define CONTENT_BROWSER_TAB_CONTENTS_TAB_CONTENTS_H_
 #pragma once
 
 #include <deque>
 #include <map>
@@ skipping 140 matching lines @@
   int32 GetMaxPageID();
 
   // Updates the max PageID to be at least the given PageID.
   void UpdateMaxPageID(int32 page_id);
 
   // Returns the site instance associated with the current page. By default,
   // there is no site instance. TabContents overrides this to provide proper
   // access to its site instance.
   virtual SiteInstance* GetSiteInstance() const;
 
+  // Returns the SiteInstance for the pending navigation, if any.  Otherwise
+  // returns the current SiteInstance.
+  SiteInstance* GetPendingSiteInstance() const;
+
   // Defines whether this tab's URL should be displayed in the browser's URL
   // bar. Normally this is true so you can see the URL. This is set to false
   // for the new tab page and related pages so that the URL bar is empty and
   // the user is invited to type into it.
   virtual bool ShouldDisplayURL();
 
   // Return whether this tab contents is loading a resource, or whether its
   // web_ui is.
   bool IsLoading() const;
 
@@ skipping 435 matching lines @@
 
   // Causes the TabContents to navigate in the right renderer to |entry|, which
   // must be already part of the entries in the navigation controller.
   // This does not change the NavigationController state.
   bool NavigateToEntry(const NavigationEntry& entry,
                        NavigationController::ReloadType reload_type);
 
   // Sets the history for this tab_contents to |history_length| entries, and
   // moves the current page_id to the last entry in the list if it's valid.
   // This is mainly used when a prerendered page is swapped into the current
-  // tab.
-  void SetHistoryLengthAndClear(int history_length);
-
+  // tab. The method is virtual for testing.
+  virtual void SetHistoryLengthAndPrune(const SiteInstance* site_instance,
+                                        int merge_history_length,
+                                        int32 minimum_page_id);
 
   // Misc non-view stuff -------------------------------------------------------
 
   // Helper functions for sending notifications.
   void NotifySwapped();
   void NotifyConnected();
   void NotifyDisconnected();
 
   // RenderViewHostDelegate ----------------------------------------------------
 
@@ skipping 221 matching lines @@
   ObserverList<TabContentsObserver> observers_;
 
   // Content restrictions, used to disable print/copy etc based on content's
   // (full-page plugins for now only) permissions.
   int content_restrictions_;
 
   DISALLOW_COPY_AND_ASSIGN(TabContents);
 };
 
 #endif  // CONTENT_BROWSER_TAB_CONTENTS_TAB_CONTENTS_H_