Remove TouchEvent interface, and rename TouchEventImpl to TouchEvent

ui/aura/root_window_host_delegate.h

Index: ui/aura/root_window_host_delegate.h
diff --git a/ui/aura/root_window_host_delegate.h b/ui/aura/root_window_host_delegate.h
index 1ebeb5feb7ef06c824c9bfeea4f63cde592138ce..6bc58522803b38052659a659536bb375b4046a64 100644
--- a/ui/aura/root_window_host_delegate.h
+++ b/ui/aura/root_window_host_delegate.h
@@ -13,7 +13,7 @@ namespace ui {
 class KeyEvent;
 class MouseEvent;
 class ScrollEvent;
-class TouchEventImpl;
+class TouchEvent;
 }
 
 namespace aura {
@@ -27,7 +27,7 @@ class AURA_EXPORT RootWindowHostDelegate {
   virtual bool OnHostKeyEvent(ui::KeyEvent* event) = 0;
   virtual bool OnHostMouseEvent(ui::MouseEvent* event) = 0;
   virtual bool OnHostScrollEvent(ui::ScrollEvent* event) = 0;
-  virtual bool OnHostTouchEvent(ui::TouchEventImpl* event) = 0;
+  virtual bool OnHostTouchEvent(ui::TouchEvent* event) = 0;
 
   virtual void OnHostLostCapture() = 0;