video_encode_accelerator.mojom: Remove deprecated functions and structures

BUG=chromium:895230
TEST=CtsMediaTestCases

Change-Id: If928fa30cf6800809242b467c472b4549926f3d0
Reviewed-on: https://chromium-review.googlesource.com/c/1325584
Reviewed-by: Pawel Osciak <posciak@chromium.org>
Reviewed-by: Greg Kerr <kerrnel@chromium.org>
Commit-Queue: Hirokazu Honda <hiroh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#607116}
6 files changed