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

chrome/browser/ui/views/frame/popup_non_client_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/popup_non_client_frame_view.h"
 
 #include "chrome/browser/ui/views/frame/browser_frame.h"
 #include "ui/base/hit_test.h"
 #include "ui/gfx/point.h"
 #include "ui/gfx/rect.h"
@@ skipping 14 matching lines @@
 }
 
 int PopupNonClientFrameView::NonClientHitTest(const gfx::Point& point) {
   return bounds().Contains(point) ? HTCLIENT : HTNOWHERE;
 }
 
 void PopupNonClientFrameView::GetWindowMask(const gfx::Size& size,
                                                     gfx::Path* window_mask) {
 }
 
+void PopupNonClientFrameView::EnableClose(bool enable) {
+}
+
 void PopupNonClientFrameView::ResetWindowControls() {
 }
 
 void PopupNonClientFrameView::UpdateWindowIcon() {
 }
 
 gfx::Rect PopupNonClientFrameView::GetBoundsForTabStrip(
     views::View* tabstrip) const {
   return gfx::Rect(0, 0, width(), tabstrip->GetPreferredSize().height());
 }
 
 int PopupNonClientFrameView::GetHorizontalTabStripVerticalOffset(
     bool restored) const {
   return 0;
 }
 
 void PopupNonClientFrameView::UpdateThrobber(bool running) {
 }