events: Update mouse-event handlers to not return EventResult.

ui/views/corewm/compound_event_filter.h

Index: ui/views/corewm/compound_event_filter.h
diff --git a/ui/views/corewm/compound_event_filter.h b/ui/views/corewm/compound_event_filter.h
index 685c606fd4d34268f6777dea861818123de29bf8..e2dba416a774b7156d5e5cf8a91c2c1a278724ee 100644
--- a/ui/views/corewm/compound_event_filter.h
+++ b/ui/views/corewm/compound_event_filter.h
@@ -64,7 +64,7 @@ class VIEWS_EXPORT CompoundEventFilter : public ui::EventHandler {
 
   // Dispatches event to additional filters.
   void FilterKeyEvent(ui::KeyEvent* event);
-  ui::EventResult FilterMouseEvent(ui::MouseEvent* event);
+  void FilterMouseEvent(ui::MouseEvent* event);
   void FilterTouchEvent(ui::TouchEvent* event);
 
   // Sets the visibility of the cursor if the event is not synthesized and
@@ -79,7 +79,7 @@ class VIEWS_EXPORT CompoundEventFilter : public ui::EventHandler {
 
   // Overridden from ui::EventHandler:
   virtual void OnKeyEvent(ui::KeyEvent* event) OVERRIDE;
-  virtual ui::EventResult OnMouseEvent(ui::MouseEvent* event) OVERRIDE;
+  virtual void OnMouseEvent(ui::MouseEvent* event) OVERRIDE;
   virtual void OnScrollEvent(ui::ScrollEvent* event) OVERRIDE;
   virtual void OnTouchEvent(ui::TouchEvent* event) OVERRIDE;
   virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE;