Add support for X11 workspaces

ui/aura/window_tree_host.cc

 // Copyright (c) 2013 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/window_tree_host.h"
 
 #include "base/thread_task_runner_handle.h"
 #include "base/trace_event/trace_event.h"
 #include "ui/aura/client/capture_client.h"
 #include "ui/aura/client/cursor_client.h"
@@ skipping 267 matching lines @@
   compositor_->SetScaleAndSize(GetDeviceScaleFactorFromDisplay(window()),
                                adjusted_size);
 
   gfx::Size layer_size = GetBounds().size();
   // The layer, and the observers should be notified of the
   // transformed size of the root window.
   UpdateRootWindowSize(layer_size);
   FOR_EACH_OBSERVER(WindowTreeHostObserver, observers_, OnHostResized(this));
 }
 
+void WindowTreeHost::OnHostWorkspaceChanged() {
+  FOR_EACH_OBSERVER(WindowTreeHostObserver, observers_,
+                    OnHostWorkspaceChanged(this));
+}
+
 void WindowTreeHost::OnHostCloseRequested() {
   FOR_EACH_OBSERVER(WindowTreeHostObserver, observers_,
                     OnHostCloseRequested(this));
 }
 
 void WindowTreeHost::OnHostActivated() {
   Env::GetInstance()->NotifyHostActivated(this);
 }
 
 void WindowTreeHost::OnHostLostWindowCapture() {
@@ skipping 16 matching lines @@
   client::CursorClient* cursor_client = client::GetCursorClient(window());
   if (cursor_client) {
     const gfx::Display& display =
         gfx::Screen::GetScreen()->GetDisplayNearestWindow(window());
     cursor_client->SetDisplay(display);
   }
   dispatcher()->OnCursorMovedToRootLocation(root_location);
 }
 
 }  // namespace aura