Fix incorrect creation of duplicate navigation entries for repeated page load failures.

content/browser/frame_host/navigation_controller_impl.h

 // Copyright 2013 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_FRAME_HOST_NAVIGATION_CONTROLLER_IMPL_H_
 #define CONTENT_BROWSER_FRAME_HOST_NAVIGATION_CONTROLLER_IMPL_H_
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
@@ skipping 181 matching lines @@
   // Takes a screenshot of the page at the current state.
   void TakeScreenshot();
 
   // Sets the screenshot manager for this NavigationControllerImpl. The
   // controller takes ownership of the screenshot manager and destroys it when
   // a new screenshot-manager is set, or when the controller is destroyed.
   // Setting a NULL manager recreates the default screenshot manager and uses
   // that.
   void SetScreenshotManager(NavigationEntryScreenshotManager* manager);
 
-  // Discards only the pending entry.
-  void DiscardPendingEntry();
+  // Discards only the pending entry. |was_failure| should be set if the pending
+  // entry is being discarded because it failed to load.
+  void DiscardPendingEntry(bool was_failure);
 
  private:
   friend class RestoreHelper;
 
   FRIEND_TEST_ALL_PREFIXES(NavigationControllerTest,
                            PurgeScreenshot);
   FRIEND_TEST_ALL_PREFIXES(TimeSmoother, Basic);
   FRIEND_TEST_ALL_PREFIXES(TimeSmoother, SingleDuplicate);
   FRIEND_TEST_ALL_PREFIXES(TimeSmoother, ManyDuplicates);
   FRIEND_TEST_ALL_PREFIXES(TimeSmoother, ClockBackwardsJump);
@@ skipping 124 matching lines @@
 
   // An entry we haven't gotten a response for yet.  This will be discarded
   // when we navigate again.  It's used only so we know what the currently
   // displayed tab is.
   //
   // This may refer to an item in the entries_ list if the pending_entry_index_
   // == -1, or it may be its own entry that should be deleted. Be careful with
   // the memory management.
   NavigationEntryImpl* pending_entry_;
 
-  // currently visible entry
+  // If a new entry fails loading, details about it are temporarily held here
+  // until the error page is shown. These variables are only valid if
+  // |failed_pending_entry_id_| is not 0.
+  //
+  // TODO(avi): We need a better way to handle the connection between failed
+  // loads and the subsequent load of the error page. This current approach has
+  // issues: 1. This might hang around longer than we'd like if there is no
+  // error page loaded, and 2. This doesn't work very well for frames.
+  // http://crbug.com/474261
+  int failed_pending_entry_id_;
+  bool failed_pending_entry_should_replace_;
+
+  // The index of the currently visible entry.
   int last_committed_entry_index_;
 
-  // index of pending entry if it is in entries_, or -1 if pending_entry_ is a
-  // new entry (created by LoadURL).
+  // The index of the pending entry if it is in entries_, or -1 if
+  // pending_entry_ is a new entry (created by LoadURL).
   int pending_entry_index_;
 
   // The index for the entry that is shown until a navigation occurs.  This is
   // used for interstitial pages. -1 if there are no such entry.
   // Note that this entry really appears in the list of entries, but only
   // temporarily (until the next navigation).  Any index pointing to an entry
   // after the transient entry will become invalid if you navigate forward.
   int transient_entry_index_;
 
   // The delegate associated with the controller. Possibly NULL during
@@ skipping 45 matching lines @@
   TimeSmoother time_smoother_;
 
   scoped_ptr<NavigationEntryScreenshotManager> screenshot_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(NavigationControllerImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_NAVIGATION_CONTROLLER_IMPL_H_