Remove vertex attrib related code in RasterDecoder.

RatserDecoder uses Skia to do rendering, and skia can restore vertex
attribs. So we don't need maintain and restore it in RasterDecoder.

Bug: 902904
Change-Id: I3e85d3960e0b782e41ae6d45c07ddf3494e63ca9
Reviewed-on: https://chromium-review.googlesource.com/c/1334201
Commit-Queue: Peng Huang <penghuang@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#607826}
3 files changed