events: Update scroll and touch handlers to not return EventResult.

ash/wm/activation_controller.cc

Index: ash/wm/activation_controller.cc
diff --git a/ash/wm/activation_controller.cc b/ash/wm/activation_controller.cc
index 274ab563d11607cb0d4076a8d777f1327726163b..55440785982e9bf233c0a0afacc8b8b6b4754216 100644
--- a/ash/wm/activation_controller.cc
+++ b/ash/wm/activation_controller.cc
@@ -282,14 +282,12 @@ ui::EventResult ActivationController::OnMouseEvent(ui::MouseEvent* event) {
   return ui::ER_UNHANDLED;
 }
 
-ui::EventResult ActivationController::OnScrollEvent(ui::ScrollEvent* event) {
-  return ui::ER_UNHANDLED;
+void ActivationController::OnScrollEvent(ui::ScrollEvent* event) {
 }
 
-ui::EventResult ActivationController::OnTouchEvent(ui::TouchEvent* event) {
+void ActivationController::OnTouchEvent(ui::TouchEvent* event) {
   if (event->type() == ui::ET_TOUCH_PRESSED)
     FocusWindowWithEvent(event);
-  return ui::ER_UNHANDLED;
 }
 
 void ActivationController::OnGestureEvent(ui::GestureEvent* event) {