Fix XferDemo by sending push button events directly to parent

Bug: skia:
Change-Id: I3141dd34a9a04c7a660000cba9e483191f28ef03
Reviewed-on: https://skia-review.googlesource.com/75362
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
1 file changed