Add GrabWindowSnapshotAsync tests

ui/views/widget/desktop_aura/desktop_root_window_host_x11.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_x11.h"
 
 #include <X11/extensions/shape.h>
 #include <X11/extensions/XInput2.h>
 #include <X11/Xatom.h>
 #include <X11/Xregion.h>
@@ skipping 124 matching lines @@
       drag_drop_client_(NULL),
       current_cursor_(ui::kCursorNull),
       native_widget_delegate_(native_widget_delegate),
       desktop_native_widget_aura_(desktop_native_widget_aura),
       content_window_(NULL),
       window_parent_(NULL),
       custom_window_shape_(NULL) {
 }
 
 DesktopWindowTreeHostX11::~DesktopWindowTreeHostX11() {
+  DestroyCompositor();
   root_window_->window()->ClearProperty(kHostForRootWindow);
   aura::client::SetWindowMoveClient(root_window_->window(), NULL);
   desktop_native_widget_aura_->OnDesktopWindowTreeHostDestroyed(root_window_);
   if (custom_window_shape_)
     XDestroyRegion(custom_window_shape_);
 }
 
 // static
 aura::Window* DesktopWindowTreeHostX11::GetContentWindowForXID(XID xid) {
   aura::RootWindow* root = aura::RootWindow::GetForAcceleratedWidget(xid);
@@ skipping 1388 matching lines @@
   if (linux_ui) {
     ui::NativeTheme* native_theme = linux_ui->GetNativeTheme();
     if (native_theme)
       return native_theme;
   }
 
   return ui::NativeTheme::instance();
 }
 
 }  // namespace views