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

ui/aura_shell/toplevel_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 "ui/aura_shell/toplevel_frame_view.h"
 
 #include "grit/ui_resources.h"
 #include "ui/aura/cursor.h"
 #include "ui/base/animation/throb_animation.h"
 #include "ui/base/hit_test.h"
@@ skipping 143 matching lines @@
     gfx::Point translated_point(point);
     View::ConvertPointToView(parent(), this, &translated_point);
     // The window controls come second.
     if (close_button_->GetMirroredBounds().Contains(translated_point))
       return HTCLOSE;
     else if (zoom_button_->GetMirroredBounds().Contains(translated_point))
       return HTMAXBUTTON;
     return HTNOWHERE;
   }
 
+  // Updates the enabled state of the close button.
+  void EnableClose(bool enable) {
+    close_button_->SetEnabled(enable);
+  }
+
   // Overridden from FrameComponent:
   virtual bool IgnoreEventsForPoint(const gfx::Point& point) OVERRIDE {
     gfx::Point translated_point(point);
     ConvertPointToView(parent(), this, &translated_point);
     if (PointIsInChildView(close_button_, translated_point))
       return false;
     if (PointIsInChildView(zoom_button_, translated_point))
       return false;
     return FrameComponent::IgnoreEventsForPoint(point);
   }
@@ skipping 215 matching lines @@
 int ToplevelFrameView::NonClientHitTest(const gfx::Point& point) {
   current_hittest_code_ = NonClientHitTestImpl(point);
   return current_hittest_code_;
 }
 
 void ToplevelFrameView::GetWindowMask(const gfx::Size& size,
                                       gfx::Path* window_mask) {
   // Nothing.
 }
 
+void ToplevelFrameView::EnableClose(bool enable) {
+  caption_->EnableClose(enable);
+}
+
 void ToplevelFrameView::ResetWindowControls() {
   NOTIMPLEMENTED();
 }
 
 void ToplevelFrameView::UpdateWindowIcon() {
   NOTIMPLEMENTED();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // ToplevelFrameView, views::View overrides:
@@ skipping 69 matching lines @@
       return aura::kCursorNorthWestResize;
     case HTTOPRIGHT:
       return aura::kCursorNorthEastResize;
     default:
       return aura::kCursorNull;
   }
 }
 
 }  // namespace internal
 }  // namespace aura_shell