Fix bug where panels sometimes don't align on bottom.

chrome/browser/ui/panels/panel_browser_window_gtk.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 CHROME_BROWSER_UI_PANELS_PANEL_BROWSER_WINDOW_GTK_H_
 #define CHROME_BROWSER_UI_PANELS_PANEL_BROWSER_WINDOW_GTK_H_
 
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop.h"
 #include "chrome/browser/ui/gtk/browser_window_gtk.h"
@@ skipping 173 matching lines @@
   // want to minimize it on subsequent mouseUp.
   // We use time interval because the window may gain focus in various ways
   // (via keyboard for example) which are not distinguishable at this point.
   // Apparently this disable interval is not affecting the user in other cases.
   base::Time disableMinimizeUntilTime_;
 
   // Used to animate the bounds change.
   scoped_ptr<ui::SlideAnimation> bounds_animator_;
   gfx::Rect animation_start_bounds_;
 
+  // This records the bounds set on the last animation progress notification.
+  // We need this for the case where a new bounds animation starts before the
+  // current one completes. In this case, we want to start the new animation
+  // from where the last one left.
+  gfx::Rect last_animation_progressed_bounds_;
+
   DISALLOW_COPY_AND_ASSIGN(PanelBrowserWindowGtk);
 };
 
 #endif  // CHROME_BROWSER_UI_PANELS_PANEL_BROWSER_WINDOW_GTK_H_