Add support for X11 workspaces

ui/views/widget/desktop_aura/desktop_native_widget_aura.cc

Index: ui/views/widget/desktop_aura/desktop_native_widget_aura.cc
diff --git a/ui/views/widget/desktop_aura/desktop_native_widget_aura.cc b/ui/views/widget/desktop_aura/desktop_native_widget_aura.cc
index e1b03bf712757295903be7e180e79d96b45327cd..204fd66e85175f66b2a0a07f3d89ed987db650fd 100644
--- a/ui/views/widget/desktop_aura/desktop_native_widget_aura.cc
+++ b/ui/views/widget/desktop_aura/desktop_native_widget_aura.cc
@@ -676,6 +676,11 @@ gfx::Rect DesktopNativeWidgetAura::GetRestoredBounds() const {
       desktop_window_tree_host_->GetRestoredBounds() : gfx::Rect();
 }
 
+int DesktopNativeWidgetAura::GetRestoredWorkspace() const {
+  return content_window_ ?
+      desktop_window_tree_host_->GetRestoredWorkspace() : -1;
+}
+
 void DesktopNativeWidgetAura::SetBounds(const gfx::Rect& bounds) {
   if (!content_window_)
     return;
@@ -1157,6 +1162,12 @@ void DesktopNativeWidgetAura::OnHostResized(const aura::WindowTreeHost* host) {
   native_widget_delegate_->OnNativeWidgetSizeChanged(new_bounds.size());
 }
 
+void DesktopNativeWidgetAura::OnHostWorkspaceChanged(
+    const aura::WindowTreeHost* host,
+    int workspace_id) {
+  native_widget_delegate_->OnNativeWidgetWorkspaceChanged(workspace_id);
+}
+
 void DesktopNativeWidgetAura::OnHostMoved(const aura::WindowTreeHost* host,
                                           const gfx::Point& new_origin) {
   TRACE_EVENT1("views", "DesktopNativeWidgetAura::OnHostMoved",