Separates out accelerator handling in windowmanager

ash/mus/window_manager.h

Index: ash/mus/window_manager.h
diff --git a/ash/mus/window_manager.h b/ash/mus/window_manager.h
index 515f4f926275f8dbbf30d0a5792ca0c95a55f59c..98730e1e6c218425a0de8b7a23a9510cf5951d0b 100644
--- a/ash/mus/window_manager.h
+++ b/ash/mus/window_manager.h
@@ -30,6 +30,7 @@ class Connector;
 namespace ash {
 namespace mus {
 
+class AcceleratorHandler;
 class RootWindowController;
 class ShadowController;
 class WindowManagerObserver;
@@ -68,14 +69,19 @@ class WindowManager : public ::ui::WindowManagerDelegate,
 
   std::set<RootWindowController*> GetRootWindowControllers();
 
+  // Returns the next accelerator namespace id by value in |id|. Returns true
+  // if there is another slot available, false if all slots are taken up.
+  bool GetNextAcceleratorNamespaceId(uint16_t* id);
+  void AddAcceleratorHandler(uint16_t id_namespace,
+                             AcceleratorHandler* handler);
+  void RemoveAcceleratorHandler(uint16_t id_namespace);
+
   void AddObserver(WindowManagerObserver* observer);
   void RemoveObserver(WindowManagerObserver* observer);
 
  private:
   friend class WmTestHelper;
 
-  void AddAccelerators();
-
   RootWindowController* CreateRootWindowController(
       ::ui::Window* window,
       const display::Display& display);
@@ -128,6 +134,9 @@ class WindowManager : public ::ui::WindowManagerDelegate,
 
   std::unique_ptr<WmLookupMus> lookup_;
 
+  std::map<uint16_t, AcceleratorHandler*> accelerator_handlers_;
+  uint16_t next_accelerator_namespace_id_ = 0u;
+
   DISALLOW_COPY_AND_ASSIGN(WindowManager);
 };