GitLab

With https://crrev.com/a9cbaa7a40e2b2723cfc2f266c42f4980038a949,
WebMediaPlayer blindly treats a resource experiencing cross-origin
redirects as TAINTED. In fact, it should be treated as TAINTED only
when its request mode is "no-cors".

The added tests are provided by hongchan@chromium.org.

Bug: 899745, 901383
Change-Id: Idb66407552085b053818f3e4a9d8d5ff3ddeaf45
Reviewed-on: https://chromium-review.googlesource.com/c/1325281Reviewed-by: Hongchan Choi <hongchan@chromium.org>
Reviewed-by: Fredrik Hubinette <hubbe@chromium.org>
Commit-Queue: Yutaka Hirano <yhirano@chromium.org>
Cr-Commit-Position: refs/heads/master@{#606681}