I think the issue is that the user may only remove their finger after they see the feedback animation while the radius of the animation grows from 0 so for most of the time the feedback animation will be covered by the user's finger.

An easy fix for this problem is just to reverse the animation, i.e. the size shrinks over time then the user will be able to see the feedback right after it is triggered.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/cdc3c1395e8cc0795cf70d9fe552e12a1036285a

commit cdc3c1395e8cc0795cf70d9fe552e12a1036285a
Author: yuweih <yuweih@chromium.org>
Date: Tue Aug 23 04:46:26 2016

[Remoting Android] Use Material Design's Ripple Expansion Function for Touch Feedback

Currently the radius of the touch feedback animation is linear to time, making
it spend the same amount of time when showing the large circle as when showing
the smaller circle.

This CL changes the radius-time function to a decelerating function as the
material design spec suggested. This will make the animation looks more rapid
given the same duration.

This CL also increases the animation duration to 300ms, which is a balanced
value for showing both simple touch and press-and-hold feedback.

BUG= 638317 

Review-Url: https://codereview.chromium.org/2265053005
Cr-Commit-Position: refs/heads/master@{#413666}

[modify] https://crrev.com/cdc3c1395e8cc0795cf70d9fe552e12a1036285a/remoting/client/gl_cursor_feedback.cc

Verified in 54.0.2840.6