Move GetCursor() method from WindowDelegate to its own delegate interface CursorDelegate.

ui/keyboard/keyboard_controller.cc

Index: ui/keyboard/keyboard_controller.cc
diff --git a/ui/keyboard/keyboard_controller.cc b/ui/keyboard/keyboard_controller.cc
index 95966147d89644c492af6be9e47eb5131752115f..fd0ac591bb4a8b31a328afca0dc523d98ed0dd88 100644
--- a/ui/keyboard/keyboard_controller.cc
+++ b/ui/keyboard/keyboard_controller.cc
@@ -84,9 +84,6 @@ class KeyboardWindowDelegate : public aura::WindowDelegate {
                                const gfx::Rect& new_bounds) OVERRIDE {
     bounds_ = new_bounds;
   }
-  virtual gfx::NativeCursor GetCursor(const gfx::Point& point) OVERRIDE {
-    return gfx::kNullCursor;
-  }
   virtual int GetNonClientComponent(const gfx::Point& point) const OVERRIDE {
     return HTNOWHERE;
   }