Rework FocusManager as FocusClient.

ui/aura/root_window.h

Index: ui/aura/root_window.h
===================================================================
--- ui/aura/root_window.h	(revision 169793)
+++ ui/aura/root_window.h	(working copy)
@@ -47,7 +47,6 @@
 
 namespace aura {
 
-class FocusManager;
 class RootWindow;
 class RootWindowHost;
 class RootWindowObserver;
@@ -85,10 +84,6 @@
   gfx::NativeCursor last_cursor() const { return last_cursor_; }
   Window* mouse_pressed_handler() { return mouse_pressed_handler_; }
 
-  void set_focus_manager(FocusManager* focus_manager) {
-    focus_manager_ = focus_manager;
-  }
-
   // Initializes the root window.
   void Init();
 
@@ -254,7 +249,6 @@
   // Overridden from Window:
   virtual bool CanFocus() const OVERRIDE;
   virtual bool CanReceiveEvents() const OVERRIDE;
-  virtual FocusManager* GetFocusManager() OVERRIDE;
 
   // Overridden from aura::client::CaptureDelegate:
   virtual void UpdateCapture(Window* old_capture, Window* new_capture) OVERRIDE;
@@ -386,7 +380,6 @@
   Window* mouse_moved_handler_;
   Window* mouse_event_dispatch_target_;
   Window* event_dispatch_target_;
-  FocusManager* focus_manager_;
 
   // The gesture_recognizer_ for this.
   scoped_ptr<ui::GestureRecognizer> gesture_recognizer_;