views: Also const-ify GetMaximumSize().

chrome/browser/ui/views/panels/panel_frame_view.cc

 // 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.
 
 #include "chrome/browser/ui/views/panels/panel_frame_view.h"
 
 #include "chrome/browser/ui/panels/panel.h"
 #include "chrome/browser/ui/panels/panel_constants.h"
 #include "chrome/browser/ui/views/panels/panel_view.h"
 #include "chrome/browser/ui/views/tab_icon_view.h"
@@ skipping 487 matching lines @@
 }
 
 const char* PanelFrameView::GetClassName() const {
   return kViewClassName;
 }
 
 gfx::Size PanelFrameView::GetMinimumSize() const {
   return panel_view_->GetMinimumSize();
 }
 
-gfx::Size PanelFrameView::GetMaximumSize() {
+gfx::Size PanelFrameView::GetMaximumSize() const {
   return panel_view_->GetMaximumSize();
 }
 
 void PanelFrameView::Layout() {
   is_frameless_ = ShouldRenderAsFrameless();
 
   // Layout the close button.
   int right = width();
   close_button_->SetBounds(
       width() - panel::kTitlebarRightPadding - panel::kPanelButtonSize,
@@ skipping 240 matching lines @@
 
   // Draw the left border.
   canvas->TileImageInt(left_image,
                        0,
                        top_left_image.height(),
                        left_image.width(),
                        height() - top_left_image.height() -
                            bottom_left_image.height());
 #endif
 }