Avoid stale navigation requests without excessive page id knowledge in the renderer process.

content/browser/web_contents/web_contents_impl.h

 // Copyright (c) 2012 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_WEB_CONTENTS_WEB_CONTENTS_IMPL_H_
 #define CONTENT_BROWSER_WEB_CONTENTS_WEB_CONTENTS_IMPL_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 593 matching lines @@
   // The callbacks can be inside of this function, or at some future time.
   //
   // The entry has a PageID of -1 if newly created (corresponding to navigation
   // to a new URL).
   //
   // If this method returns false, then the navigation is discarded (equivalent
   // to calling DiscardPendingEntry on the NavigationController).
   bool NavigateToPendingEntry(
       NavigationController::ReloadType reload_type) override;
 
-  // Sets the history for this WebContentsImpl 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. The method is virtual for testing.
-  void SetHistoryLengthAndPrune(const SiteInstance* site_instance,
-                                int merge_history_length,
-                                int32 minimum_page_id) override;
+  // Sets the history for this WebContentsImpl to |history_length| entries, with
+  // an offset of |history_offset|.
+  void SetHistoryOffsetAndLength(int history_offset,
+                                 int history_length) override;
 
   // Called by InterstitialPageImpl when it creates a RenderFrameHost.
   void RenderFrameForInterstitialPageCreated(
       RenderFrameHost* render_frame_host) override;
 
   // Sets the passed interstitial as the currently showing interstitial.
   // No interstitial page should already be attached.
   void AttachInterstitialPage(InterstitialPageImpl* interstitial_page) override;
 
   // Unsets the currently showing interstitial.
@@ skipping 248 matching lines @@
   // Tracking loading progress -------------------------------------------------
 
   // Resets the tracking state of the current load.
   void ResetLoadProgressState();
 
   // Calculates the progress of the current load and notifies the delegate.
   void SendLoadProgressChanged();
 
   // Misc non-view stuff -------------------------------------------------------
 
+  // Sets the history for a specified RenderViewHost to |history_length|
+  // entries, with an offset of |history_offset|.
+  void SetHistoryOffsetAndLengthForView(RenderViewHost* render_view_host,
+                                        int history_offset,
+                                        int history_length);
+
   // Helper functions for sending notifications.
   void NotifyViewSwapped(RenderViewHost* old_host, RenderViewHost* new_host);
   void NotifyFrameSwapped(RenderFrameHost* old_host, RenderFrameHost* new_host);
   void NotifyDisconnected();
 
   void SetEncoding(const std::string& encoding);
 
   // TODO(creis): This should take in a FrameTreeNode to know which node's
   // render manager to return.  For now, we just return the root's.
   RenderFrameHostManager* GetRenderManager() const;
@@ skipping 329 matching lines @@
   bool virtual_keyboard_requested_;
 
   base::WeakPtrFactory<WebContentsImpl> loading_weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebContentsImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_WEB_CONTENTS_WEB_CONTENTS_IMPL_H_