Mac: Some clang appeasing.

chrome/default_plugin/plugin_impl_gtk.h

 // Copyright (c) 2010 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_DEFAULT_PLUGIN_PLUGIN_IMPL_GTK_H_
 #define CHROME_DEFAULT_PLUGIN_PLUGIN_IMPL_GTK_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 144 matching lines @@
   // state of the plugin installer.
   void set_plugin_installer_state(PluginInstallerState new_state) {
     plugin_installer_state_ = new_state;
   }
 
   PluginInstallerState plugin_installer_state() const {
     return plugin_installer_state_;
   }
 
   // Getter for the NPP instance member.
-  const NPP instance() const {
+  NPP instance() const {
     return instance_;
   }
 
   // Returns whether or not the UI layout is right-to-left (such as Hebrew or
   // Arabic).
   bool IsRTLLayout() const;
 
  protected:
   // Displays the plugin install confirmation dialog.
   void ShowInstallDialog();
@@ skipping 99 matching lines @@
   std::string mime_type_;
   // The current state of the plugin installer.
   PluginInstallerState plugin_installer_state_;
   // GtkPlug containing everything in the plugin.
   GtkWidget* container_;
 
   DISALLOW_COPY_AND_ASSIGN(PluginInstallerImpl);
 };
 
 #endif  // CHROME_DEFAULT_PLUGIN_PLUGIN_IMPL_GTK_H_