Fix <object data=> YouTube Flash rewrites.

Fix <object data=> YouTube Flash rewrites.

Some YouTube videos are embedded via <object data="http://www.youtube.com/v/AABBCCDD">.
Chrome currently only rewrites embeds that use <embed src="http://www.youtube.com/v/AABBCCDD">
The CL adds the logic for rewriting YouTube Flash plugin embed URLs with HTML5 embeds to the
HTMLObjectElement (this matches Firefox behavior).

Trying to reland https://codereview.chromium.org/2416253002.
Split the browser test into 10 separate test cases trying to avoid OOM on Debug ChromiumOS builder.

BUG=655988
TEST=manual + updated browser tests

Review-Url: https://chromiumcodereview.appspot.com/2424293002
Cr-Commit-Position: refs/heads/master@{#426223}
(cherry picked from commit 3efdec3c23c4fb82b88803d65daf114beae5553d)

[whywhat, 2016-10-19 21:43:37]

The CQ bit was checked by avayvod@chromium.org

[commit-bot: I haz the power, 2016-10-19 21:44:43]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-10-19 21:44:43]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-10-19 21:44:44]

No L-G-T-M from a valid reviewer yet. 
CQ run can only be started by full committers or once the patch has
received an L-G-T-M from a full committer.
Even if an L-G-T-M may have been provided, it was from a non-committer,
_not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.