Make sure that the pressure is always 0 for pointerup events

ui/events/android/motion_event_android.cc

Index: ui/events/android/motion_event_android.cc
diff --git a/ui/events/android/motion_event_android.cc b/ui/events/android/motion_event_android.cc
index ee645bfc80e25d19e1596ce70994b404e7a33867..9815f2c69eff995fb32d546d23a74b96469beb64 100644
--- a/ui/events/android/motion_event_android.cc
+++ b/ui/events/android/motion_event_android.cc
@@ -304,6 +304,8 @@ float MotionEventAndroid::GetPressure(size_t pointer_index) const {
   // accessed at most once per event instance).
   if (!event_.obj())
     return 0.f;
+  if (cached_action_ == ACTION_UP)

[mustaq, 2017/02/17 16:07:18]

I guess this came from a previous mistake in Line 232 above: cached_action_ is
of type MotionEvent::Action, so should always be compared/assigned to
MotionEvent::ACTION_UP or MotionEventAndroid::ACTION_UP. ACTION_UP from Java
side is different from MotionEvent::ACTION_UP afaik.

How come we never saw the problem in Line 232? Tim, any idea?

[mustaq, 2017/02/17 16:18:51]

I have got the answer why we didn't hit Line 232 before ---
ACTION_POINTER_DOWN/UP values just happen to match in these two "definitions":
  -
https://developer.android.com/reference/android/view/MotionEvent.html#ACTION_...
  -
https://cs.chromium.org/chromium/src/ui/events/gesture_detection/motion_event...

Lan, please change this line and Line 232 as well to use MotionEvent::ACTION_*
instead.

And please confirm that Android Chromium build works for pointerup.

[lanwei, 2017/02/21 17:47:06]

Acknowledged.

+    return 0.f;
   return Java_MotionEvent_getPressureF_I(AttachCurrentThread(), event_,
                                          pointer_index);
 }