Replace PruneAllButActive with PruneAllButVisible.

content/browser/web_contents/navigation_controller_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_NAVIGATION_CONTROLLER_IMPL_H_
 #define CONTENT_BROWSER_WEB_CONTENTS_NAVIGATION_CONTROLLER_IMPL_H_
 
 #include "build/build_config.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
@@ skipping 71 matching lines @@
   virtual bool IsInitialNavigation() const OVERRIDE;
   virtual void Reload(bool check_for_repost) OVERRIDE;
   virtual void ReloadIgnoringCache(bool check_for_repost) OVERRIDE;
   virtual void ReloadOriginalRequestURL(bool check_for_repost) OVERRIDE;
   virtual void NotifyEntryChanged(const NavigationEntry* entry,
                                  int index) OVERRIDE;
   virtual void CopyStateFrom(
       const NavigationController& source) OVERRIDE;
   virtual void CopyStateFromAndPrune(
       NavigationController* source) OVERRIDE;
-  virtual void PruneAllButActive() OVERRIDE;
+  virtual bool CanPruneAllButVisible() OVERRIDE;
+  virtual void PruneAllButVisible() OVERRIDE;
   virtual void ClearAllScreenshots() OVERRIDE;
 
   // The session storage namespace that all child RenderViews belonging to
   // |instance| should use.
   SessionStorageNamespace* GetSessionStorageNamespace(
       SiteInstance* instance);
 
   // Returns the index of the specified entry, or -1 if entry is not contained
   // in this NavigationController.
   int GetIndexOfEntry(const NavigationEntryImpl* entry) const;
@@ skipping 183 matching lines @@
   // Discards the pending and transient entries.
   void DiscardNonCommittedEntriesInternal();
 
   // Discards the transient entry.
   void DiscardTransientEntry();
 
   // If we have the maximum number of entries, remove the oldest one in
   // preparation to add another.
   void PruneOldestEntryIfFull();
 
-  // Removes all the entries except the active entry. If there is a new pending
-  // navigation it is preserved. In contrast to PruneAllButActive() this does
-  // not update the session history of the RenderView.
-  void PruneAllButActiveInternal();
+  // Removes all entries except the last committed entry.  If there is a new
+  // pending navigation it is preserved. In contrast to PruneAllButVisible()
+  // this does not update the session history of the RenderView.  Callers
+  // must ensure that |CanPruneAllButVisible| returns true before calling this.
+  void PruneAllButVisibleInternal();
 
   // Returns true if the navigation is redirect.
   bool IsRedirect(const ViewHostMsg_FrameNavigate_Params& params);
 
   // Returns true if the navigation is likley to be automatic rather than
   // user-initiated.
   bool IsLikelyAutoNavigation(base::TimeTicks now);
 
   // Inserts up to |max_index| entries from |source| into this. This does NOT
   // adjust any of the members that reference entries_
@@ skipping 83 matching lines @@
   TimeSmoother time_smoother_;
 
   scoped_ptr<WebContentsScreenshotManager> screenshot_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(NavigationControllerImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_WEB_CONTENTS_NAVIGATION_CONTROLLER_IMPL_H_