DevTools: check filmStripModel for screenshots

filmStripModel may contain screenshots  even if framesModel does
not contain frames.

R=alph@chromium.org

Change-Id: I6ce986815fb6e330062759c54c2551b4c6a09a4e
Reviewed-on: https://chromium-review.googlesource.com/c/1379320
Reviewed-by: Alexei Filippov <alph@chromium.org>
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#616983}
1 file changed