[webkit-reviews] review requested: [Bug 211645] Enable the mock video presentation mode in related layout tests and fix test failures : [Attachment 398985] WIP patch v4

[bugzilla-daemon at webkit.org]

Peng Liu <peng.liu6 at apple.com> has asked  for review:
Bug 211645: Enable the mock video presentation mode in related layout tests and
fix test failures
https://bugs.webkit.org/show_bug.cgi?id=211645

Attachment 398985: WIP patch v4

https://bugs.webkit.org/attachment.cgi?id=398985&action=review