Convert Aura to use ui::Event.

ui/aura/client/activation_delegate.h

Index: ui/aura/client/activation_delegate.h
===================================================================
--- ui/aura/client/activation_delegate.h	(revision 150582)
+++ ui/aura/client/activation_delegate.h	(working copy)
@@ -7,8 +7,11 @@
 
 #include "ui/aura/aura_export.h"
 
+namespace ui {
+class Event;
+}
+
 namespace aura {
-class Event;
 class Window;
 namespace client {
 
@@ -20,7 +23,7 @@
   // event supplied if the activation is the result of a mouse, or the touch
   // event if the activation is the result of a touch, or NULL if activation is
   // attempted for another reason.
-  virtual bool ShouldActivate(const Event* event) = 0;
+  virtual bool ShouldActivate(const ui::Event* event) = 0;
 
   // Sent when the window is activated.
   virtual void OnActivated() = 0;