Make sure that the pressure is always 0 for pointerup events

ui/events/android/motion_event_android.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/events/android/motion_event_android.h"
 
 #include <android/input.h>
 
 #include <cmath>
 
@@ skipping 286 matching lines @@
       AttachCurrentThread(), event_, pointer_index));
 }
 
 float MotionEventAndroid::GetPressure(size_t pointer_index) const {
   DCHECK_LT(pointer_index, cached_pointer_count_);
   // Note that this early return is a special case exercised only in testing, as
   // caching the pressure values is not a worthwhile optimization (they're
   // 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);
 }
 
 float MotionEventAndroid::GetTilt(size_t pointer_index) const {
   DCHECK_LT(pointer_index, cached_pointer_count_);
   if (pointer_index < MAX_POINTERS_TO_CACHE)
     return cached_pointers_[pointer_index].tilt;
   if (!event_.obj())
     return 0.f;
@@ skipping 63 matching lines @@
       gfx::PointF(ToDips(pointer.pos_x_pixels), ToDips(pointer.pos_y_pixels));
   result.touch_major = ToDips(pointer.touch_major_pixels);
   result.touch_minor = ToDips(pointer.touch_minor_pixels);
   result.orientation = ToValidFloat(pointer.orientation_rad);
   result.tilt = ToValidFloat(pointer.tilt_rad);
   result.tool_type = FromAndroidToolType(pointer.tool_type);
   return result;
 }
 
 }  // namespace content