Moves WorkspaceController to ash/common

ash/common/root_window_controller_common.h

Index: ash/common/root_window_controller_common.h
diff --git a/ash/common/root_window_controller_common.h b/ash/common/root_window_controller_common.h
index 5b38c4d632d873254ddd558a075a028c2a142cf3..90525ec1986aef9c823596b13c87156ad7d23e1d 100644
--- a/ash/common/root_window_controller_common.h
+++ b/ash/common/root_window_controller_common.h
@@ -5,12 +5,15 @@
 #ifndef ASH_COMMON_ROOT_WINDOW_CONTROLLER_COMMON_H_
 #define ASH_COMMON_ROOT_WINDOW_CONTROLLER_COMMON_H_
 
+#include <memory>
+
 #include "ash/ash_export.h"
 #include "base/macros.h"
 
 namespace ash {
 
 class WmWindow;
+class WorkspaceController;
 
 namespace wm {
 class RootWindowLayoutManager;
@@ -30,15 +33,23 @@ class ASH_EXPORT RootWindowControllerCommon {
   // Creates the LayoutManagers for the windows created by CreateContainers().
   void CreateLayoutManagers();
 
+  void DeleteWorkspaceController();
+
   wm::RootWindowLayoutManager* root_window_layout() {
     return root_window_layout_;
   }
 
+  WorkspaceController* workspace_controller() {
+    return workspace_controller_.get();
+  }
+
  private:
   WmWindow* root_;
 
   wm::RootWindowLayoutManager* root_window_layout_;
 
+  std::unique_ptr<WorkspaceController> workspace_controller_;
+
   DISALLOW_COPY_AND_ASSIGN(RootWindowControllerCommon);
 };