Add UseCounters for Element.offset*

Add UseCounters for Element.offset*

Add HTMLElement.offset* (which is per spec) to shadow Element.offset*,
so that the new counters will only trigger for non-HTML elements.

It seems likely that usage could be high without actually implying that
removal would break anything, but wait to see the data...

BUG=463116
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=191864

[philipj_slow, 2015-03-13 04:45:04]

philipj@opera.com changed reviewers:
+ haraken@chromium.org

[philipj_slow, 2015-03-13 04:45:04]

PTAL

[haraken, 2015-03-13 04:50:02]

LGTM

[haraken, 2015-03-13 04:50:28]

I guess the counter could be very high though.

[vivekg, 2015-03-13 04:50:32]

vivekg@chromium.org changed reviewers:
+ vivekg@chromium.org

[vivekg, 2015-03-13 04:50:33]

lgtm

[philipj_slow, 2015-03-13 04:54:32]

The CQ bit was checked by philipj@opera.com

[commit-bot: I haz the power, 2015-03-13 04:54:45]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1007683002/1

[philipj_slow, 2015-03-13 04:56:18]

On 2015/03/13 04:50:28, haraken wrote:
> I guess the counter could be very high though.

Yeah, quite possibly.

[commit-bot: I haz the power, 2015-03-13 12:03:45]

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

[commit-bot: I haz the power, 2015-03-13 12:03:46]

Try jobs failed on following builders:
  linux_blink_rel on tryserver.blink (JOB_FAILED,
http://build.chromium.org/p/tryserver.blink/builders/linux_blink_rel/builds/5...)

[philipj_slow, 2015-03-13 16:22:32]

update test expectations

[philipj_slow, 2015-03-13 16:22:46]

The CQ bit was checked by philipj@opera.com

[philipj_slow, 2015-03-13 16:22:46]

The patchset sent to the CQ was uploaded after l-g-t-m from
haraken@chromium.org, vivekg@chromium.org
Link to the patchset: https://codereview.chromium.org/1007683002/#ps20001
(title: "update test expectations")

[commit-bot: I haz the power, 2015-03-13 16:22:55]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1007683002/20001

[commit-bot: I haz the power, 2015-03-13 19:42:06]

Committed patchset #2 (id:20001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=191864