Revert EnableClose() removal and related crash fixes. I don't understand the crashes here, and th...

chrome/browser/ui/views/frame/opaque_browser_frame_view.cc

 // 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.
 
 #include "chrome/browser/ui/views/frame/opaque_browser_frame_view.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/command_line.h"
@@ skipping 362 matching lines @@
 void OpaqueBrowserFrameView::GetWindowMask(const gfx::Size& size,
                                            gfx::Path* window_mask) {
   DCHECK(window_mask);
 
   if (frame()->IsMaximized() || frame()->IsFullscreen())
     return;
 
   views::GetDefaultWindowMask(size, window_mask);
 }
 
+void OpaqueBrowserFrameView::EnableClose(bool enable) {
+  close_button_->SetEnabled(enable);
+}
+
 void OpaqueBrowserFrameView::ResetWindowControls() {
   restore_button_->SetState(views::CustomButton::BS_NORMAL);
   minimize_button_->SetState(views::CustomButton::BS_NORMAL);
   maximize_button_->SetState(views::CustomButton::BS_NORMAL);
   // The close button isn't affected by this constraint.
 }
 
 void OpaqueBrowserFrameView::UpdateWindowIcon() {
   window_icon_->SchedulePaint();
 }
@@ skipping 739 matching lines @@
 
 gfx::Rect OpaqueBrowserFrameView::CalculateClientAreaBounds(int width,
                                                             int height) const {
   int top_height = NonClientTopBorderHeight(false);
   int border_thickness = NonClientBorderThickness();
   return gfx::Rect(border_thickness, top_height,
                    std::max(0, width - (2 * border_thickness)),
                    std::max(0, height - GetReservedHeight() -
                        top_height - border_thickness));
 }