Add GrabWindowSnapshotAsync tests

ui/views/widget/desktop_aura/desktop_root_window_host_win.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 "ui/views/widget/desktop_aura/desktop_root_window_host_win.h"
 
 #include "base/win/metro.h"
 #include "third_party/skia/include/core/SkPath.h"
 #include "third_party/skia/include/core/SkRegion.h"
 #include "ui/aura/client/aura_constants.h"
@@ skipping 70 matching lines @@
       content_window_(NULL),
       drag_drop_client_(NULL),
       should_animate_window_close_(false),
       pending_close_(false),
       has_non_client_view_(false),
       tooltip_(NULL),
       is_cursor_visible_(true) {
 }
 
 DesktopWindowTreeHostWin::~DesktopWindowTreeHostWin() {
+  DestroyCompositor();
   // WARNING: |content_window_| has been destroyed by the time we get here.
   desktop_native_widget_aura_->OnDesktopWindowTreeHostDestroyed(
       root_window_);
 }
 
 // static
 aura::Window* DesktopWindowTreeHostWin::GetContentWindowForHWND(HWND hwnd) {
   aura::RootWindow* root = aura::RootWindow::GetForAcceleratedWidget(hwnd);
   return root ? root->window()->GetProperty(kContentWindowForRootWindow) : NULL;
 }
@@ skipping 883 matching lines @@
 
 // static
 DesktopWindowTreeHost* DesktopWindowTreeHost::Create(
     internal::NativeWidgetDelegate* native_widget_delegate,
     DesktopNativeWidgetAura* desktop_native_widget_aura) {
   return new DesktopWindowTreeHostWin(native_widget_delegate,
                                       desktop_native_widget_aura);
 }
 
 }  // namespace views