Move IN_OVERFLOW from Panel::ExpansionState to new enum.

chrome/browser/ui/panels/panel_overflow_strip.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_PANELS_PANEL_OVERFLOW_STRIP_H_
 #define CHROME_BROWSER_UI_PANELS_PANEL_OVERFLOW_STRIP_H_
 #pragma once
 
 #include <vector>
 #include "chrome/browser/ui/panels/panel.h"
@@ skipping 20 matching lines @@
   // |display_area| is in screen coordinates.
   void SetDisplayArea(const gfx::Rect& display_area);
 
   // Adds a panel to the strip.
   void AddPanel(Panel* panel);
 
   // Returns |false| if the panel is not in the strip.
   bool Remove(Panel* panel);
   void RemoveAll();
 
-  // Called when a panel's expansion state changes.
-  void OnPanelExpansionStateChanged(Panel* panel);
+  // Called when a panel's layout state changes.
+  void OnPanelLayoutStateChanged(Panel* panel, Panel::LayoutState old_state);
 
   // Called when a panel is starting/stopping drawing an attention.
   void OnPanelAttentionStateChanged(Panel* panel);
 
   // Refreshes the layouts for all panels to reflect any possible changes.
   void Refresh();
 
   void OnFullScreenModeChanged(bool is_full_screen);
 
   int num_panels() const { return static_cast<int>(panels_.size()); }
@@ skipping 87 matching lines @@
   int overflow_hover_animator_start_width_;
   int overflow_hover_animator_end_width_;
 
   // Invalid panel index.
   static const size_t kInvalidPanelIndex = static_cast<size_t>(-1);
 
   DISALLOW_COPY_AND_ASSIGN(PanelOverflowStrip);
 };
 
 #endif  // CHROME_BROWSER_UI_PANELS_PANEL_OVERFLOW_STRIP_H_