Remove beforeload events.

Remove beforeload events.

This feature makes the insertedInto tree walk much more complicated and
is the source of security bugs. We've had it disabled behind a flag for a
while now and not seen complaints or bugs from users.

BUG=333318
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=169994

[abarth-chromium, 2014-03-25 23:19:09]

lgtm

[esprehn, 2014-03-25 23:21:30]

The CQ bit was checked by esprehn@chromium.org

[commit-bot: I haz the power, 2014-03-25 23:21:41]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/esprehn@chromium.org/205523003/30001

[commit-bot: I haz the power, 2014-03-25 23:57:46]

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

[commit-bot: I haz the power, 2014-03-25 23:57:47]

Try jobs failed on following builders:
  tryserver.blink on linux_blink_rel

[esprehn, 2014-03-26 00:06:45]

The CQ bit was checked by esprehn@chromium.org

[commit-bot: I haz the power, 2014-03-26 00:06:47]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/esprehn@chromium.org/205523003/130001

[commit-bot: I haz the power, 2014-03-26 01:12:21]

Change committed as 169994

[abarth-chromium, 2014-03-26 05:25:14]

\o/

[philipj_slow, 2014-03-26 13:11:04]

Yes please! Thank you abarth!

[philipj_slow, 2014-03-26 13:14:07]

Oops, also thanks to esprehn who actually submitted the CL :)