Don't consume mouse events in SkottieSlide

We want to togle inval display on click, but if we always consume the
event we disable pan/zoom in viewer.

TBR=

Change-Id: I1f785883252c4f4a09fd35d4a05485849bf7e8ef
Reviewed-on: https://skia-review.googlesource.com/109084
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>
1 file changed