use enum to specify deviceSource for fling animation.

content/browser/renderer_host/input/input_router_impl.cc

Index: content/browser/renderer_host/input/input_router_impl.cc
diff --git a/content/browser/renderer_host/input/input_router_impl.cc b/content/browser/renderer_host/input/input_router_impl.cc
index 5167b266b5b26c2a18945e8c0c48c8bd556f727f..b3ca20fca57b435ed8bdd434fa957d9a3e887096 100644
--- a/content/browser/renderer_host/input/input_router_impl.cc
+++ b/content/browser/renderer_host/input/input_router_impl.cc
@@ -181,7 +181,7 @@ void InputRouterImpl::SendGestureEvent(
   if (touch_action_filter_.FilterGestureEvent(&gesture_event.event))
     return;
 
-  if (gesture_event.event.sourceDevice == WebGestureEvent::Touchscreen)
+  if (gesture_event.event.sourceDevice == blink::WebGestureDeviceTouchpad)
     touch_event_queue_.OnGestureScrollEvent(gesture_event);
 
   if (!IsInOverscrollGesture() &&
@@ -239,7 +239,7 @@ void InputRouterImpl::SendTouchEventImmediately(
 void InputRouterImpl::SendGestureEventImmediately(
     const GestureEventWithLatencyInfo& gesture_event) {
   if (gesture_event.event.type == WebInputEvent::GesturePinchUpdate &&
-      gesture_event.event.sourceDevice == WebGestureEvent::Touchpad) {
+      gesture_event.event.sourceDevice == blink::WebGestureDeviceTouchpad) {
     SendSyntheticWheelEventForPinch(gesture_event);
     return;
   }