commit c9e12fb8f608b3d0e204b167459bf9ea999e068c
author xlai <xlai@chromium.org> Mon Oct 24 21:19:56 2016
committer Commit bot <commit-bot@chromium.org> Mon Oct 24 21:26:19 2016
tree 5e6d0febb6d9f99ffdf080f6e1b8b15a1a733870
parent a77a4ddde837ba57fca3195127cd4f1ad8f96eab

Implement convertToBlob() in OffscreenCanvas

This CL implements convertToBlob on OffscreenCanvas for both
worker and main threads.

The OffscreenCanvasRenderingContext2D cases are complete.
For the Webgl rendering context, currently convertToBlob()
can only work for PNG image type.

BUG=563830
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.win:win_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2420203002
Cr-Commit-Position: refs/heads/master@{#427153}