Enable user resizing for docked Panels (GTK and Mac).

chrome/browser/ui/panels/panel.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_H_
 #define CHROME_BROWSER_UI_PANELS_PANEL_H_
 #pragma once
 
 #include "chrome/browser/ui/browser_window.h"
 
@@ skipping 241 matching lines @@
 
   ExpansionState expansion_state() const { return expansion_state_; }
   const gfx::Size& min_size() const { return min_size_; }
   const gfx::Size& max_size() const { return max_size_; }
   bool auto_resizable() const { return auto_resizable_; }
 
   bool in_preview_mode() const { return in_preview_mode_; }
 
   bool draggable() const;
 
-  bool CanResizeByMouse() const;
+  panel::Resizability CanResizeByMouse() const;
 
   AttentionMode attention_mode() const { return attention_mode_; }
   void set_attention_mode(AttentionMode attention_mode) {
     attention_mode_ = attention_mode;
   }
 
   // The restored size is the size of the panel when it is expanded.
   gfx::Size restored_size() const { return restored_size_; }
   void set_restored_size(const gfx::Size& size) { restored_size_ = size; }
 
@@ skipping 104 matching lines @@
   AttentionMode attention_mode_;
 
   ExpansionState expansion_state_;
 
   content::NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(Panel);
 };
 
 #endif  // CHROME_BROWSER_UI_PANELS_PANEL_H_