Add option to disallow the discarding of a tab that was previously discarded.

chrome/browser/ui/tabs/tab_strip_model.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 CHROME_BROWSER_UI_TABS_TAB_STRIP_MODEL_H_
 #define CHROME_BROWSER_UI_TABS_TAB_STRIP_MODEL_H_
 
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 300 matching lines @@
   // class for details on this.
   void SetTabPinned(int index, bool pinned);
 
   // Returns true if the tab at |index| is pinned.
   // See description above class for details on pinned tabs.
   bool IsTabPinned(int index) const;
 
   // Returns true if the tab at |index| is blocked by a tab modal dialog.
   bool IsTabBlocked(int index) const;
 
-  // Returns true if the WebContents at |index| has been discarded to
-  // save memory.  See DiscardWebContentsAt() for details.
-  bool IsTabDiscarded(int index) const;
-
   // Returns the index of the first tab that is not a pinned tab. This returns
   // |count()| if all of the tabs are pinned tabs, and 0 if none of the tabs are
   // pinned tabs.
   int IndexOfFirstNonPinnedTab() const;
 
   // Returns a valid index for inserting a new tab into this model. |index| is
   // the proposed index and |pinned_tab| is true if inserting a tab will become
   // pinned (pinned). If |pinned_tab| is true, the returned index is between 0
   // and IndexOfFirstNonPinnedTab. If |pinned_tab| is false, the returned index
   // is between IndexOfFirstNonPinnedTab and count().
@@ skipping 224 matching lines @@
 
   // TODO(sky): remove this; used for debugging 291265.
   bool in_notify_;
 
   base::WeakPtrFactory<TabStripModel> weak_factory_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(TabStripModel);
 };
 
 #endif  // CHROME_BROWSER_UI_TABS_TAB_STRIP_MODEL_H_