GitLab

The compatibility layer has been removed upstream:
https://gerrit.chromium.org/gerrit/gitweb?p=webm%2Flibvpx.git;a=commit;h=9cdaa3d72eade9ad162ef8f78a93bd8f85c6de10

BUG=webrtc:3839

Review URL: https://codereview.chromium.org/590363002

Cr-Commit-Position: refs/heads/master@{#296098}