Acceleration smoothing works for zero-length moves

Remove filtering of zero-length moves from the immediate interpreter so
the acceleration smoothing filter can see them and apply smoothing.
Zero-length moves are now filtered after acceleration smoothing.

BUG=b:64302878
TEST=made touchtest from feedback log with uneven reporting, including
     some zero-length moves. The filter improved performance.

Change-Id: Ia96765e5c2ea6134a08a9cca68e88ab6095b60de
Reviewed-on: https://chromium-review.googlesource.com/610477
Reviewed-by: Andrew de los Reyes <adlr@chromium.org>
Tested-by: Andrew de los Reyes <adlr@chromium.org>
Trybot-Ready: Andrew de los Reyes <adlr@chromium.org>
Commit-Queue: Andrew de los Reyes <adlr@chromium.org>
2 files changed