Remove ui::TouchEvent -> blink::WebTouchEvent conversion methods.

ui/events/gestures/motion_event_aura.cc

Index: ui/events/gestures/motion_event_aura.cc
diff --git a/ui/events/gestures/motion_event_aura.cc b/ui/events/gestures/motion_event_aura.cc
index bfe3321bed42f0972e1430cc80ca67c64677c202..7e894dd7417c60a145cc0a1812a24deedd532096 100644
--- a/ui/events/gestures/motion_event_aura.cc
+++ b/ui/events/gestures/motion_event_aura.cc
@@ -82,8 +82,10 @@ MotionEvent::Action MotionEventAura::GetAction() const {
 }
 
 int MotionEventAura::GetActionIndex() const {
-  DCHECK(cached_action_ == ACTION_POINTER_DOWN ||
-         cached_action_ == ACTION_POINTER_UP);
+  if (cached_action_ != ACTION_POINTER_DOWN &&
+      cached_action_ != ACTION_POINTER_UP) {
+    return -1;
+  }
   DCHECK_GE(cached_action_index_, 0);
   DCHECK_LT(cached_action_index_, static_cast<int>(pointer_count_));
   return cached_action_index_;