Add ShellAcceleratorController that managers global keyboard accelerators.

ui/aura/desktop.h

Index: ui/aura/desktop.h
diff --git a/ui/aura/desktop.h b/ui/aura/desktop.h
index 8ba752a5778a636f530016c4533eac1bbd2ceab2..d5970be4971976e98b83d7f5c331cc27fa16c9d6 100644
--- a/ui/aura/desktop.h
+++ b/ui/aura/desktop.h
@@ -16,6 +16,7 @@
 #include "ui/aura/focus_manager.h"
 #include "ui/aura/window.h"
 #include "ui/base/events.h"
+#include "ui/base/models/accelerator.h"
 #include "ui/gfx/compositor/compositor.h"
 #include "ui/gfx/compositor/layer_animation_observer.h"
 #include "ui/gfx/native_widget_types.h"
@@ -26,6 +27,7 @@ class Size;
 }
 
 namespace ui {
+class AcceleratorManager;
 class LayerAnimationSequence;
 class Transform;
 }
@@ -44,7 +46,8 @@ class TouchEvent;
 class AURA_EXPORT Desktop : public ui::CompositorDelegate,
                             public Window,
                             public internal::FocusManager,
-                            public ui::LayerAnimationObserver {
+                            public ui::LayerAnimationObserver,
+                            public ui::AcceleratorTarget {
  public:
   Desktop();
   virtual ~Desktop();
@@ -125,6 +128,12 @@ class AURA_EXPORT Desktop : public ui::CompositorDelegate,
   // Are any mouse buttons currently down?
   bool IsMouseButtonDown() const;
 
+  // Register accelerators for the desktop.
+  void RegisterAccelerators(ui::AcceleratorManager* accelerator_manager);
+
+  // Overridden from ui::AcceleratorTarget.
+  virtual bool AcceleratorPressed(const ui::Accelerator& accelerator) OVERRIDE;
+
   // Capture -------------------------------------------------------------------
 
   // Sets capture to the specified window.