Remove TouchEvent interface, and rename TouchEventImpl to TouchEvent

ash/wm/workspace/frame_maximize_button.cc

Index: ash/wm/workspace/frame_maximize_button.cc
diff --git a/ash/wm/workspace/frame_maximize_button.cc b/ash/wm/workspace/frame_maximize_button.cc
index ba2281b12086186ce90cbfa6b4b857938ec00690..33cdbf1b47814fccf18dd864f8e38788fd529ca2 100644
--- a/ash/wm/workspace/frame_maximize_button.cc
+++ b/ash/wm/workspace/frame_maximize_button.cc
@@ -49,7 +49,7 @@ class FrameMaximizeButton::EscapeEventFilter : public aura::EventFilter {
                                    ui::MouseEvent* event) OVERRIDE;
   virtual ui::TouchStatus PreHandleTouchEvent(
       aura::Window* target,
-      ui::TouchEventImpl* event) OVERRIDE;
+      ui::TouchEvent* event) OVERRIDE;
   virtual ui::GestureStatus PreHandleGestureEvent(
       aura::Window* target,
       ui::GestureEventImpl* event) OVERRIDE;
@@ -88,7 +88,7 @@ bool FrameMaximizeButton::EscapeEventFilter::PreHandleMouseEvent(
 
 ui::TouchStatus FrameMaximizeButton::EscapeEventFilter::PreHandleTouchEvent(
     aura::Window* target,
-    ui::TouchEventImpl* event) {
+    ui::TouchEvent* event) {
   return ui::TOUCH_STATUS_UNKNOWN;
 }