GitLab

This CL replaces all uses of IsSupportedKeySystemWithMediaMimeType() with the new KeySystems method, IsSupportedCodecCombination(). This new method implements the unprefixed algorithm more faithfully.

BUG=457386,417461

Review URL: https://codereview.chromium.org/1022823008

Cr-Commit-Position: refs/heads/master@{#322283}