Never (re)start NavigatorGamepad platform event updating once detached.

Never (re)start NavigatorGamepad platform event updating once detached.

Extend r187811 to always apply; notifications (event listener additions
or page visibility) may in boundary cases also be delivered once we
are in a frame-detached state. Do not (re)start platform event updating
in that case, as the follow-on sampling depends on being in a non-detached
state.

This is (flakily) invariant on Oilpan being enabled, or not.

R=haraken
BUG=357071
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=188893

[sof, 2015-01-23 13:18:54]

sigbjornf@opera.com changed reviewers:
+ haraken@chromium.org, mkwst@chromium.org

[sof, 2015-01-23 13:18:55]

Please take a look.

An older problem, not due to the switch made in
https://codereview.chromium.org/826223002

[haraken, 2015-01-23 14:58:24]

LGTM

[sof, 2015-01-23 15:04:14]

The CQ bit was checked by sigbjornf@opera.com

[commit-bot: I haz the power, 2015-01-23 15:04:46]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/868023003/1

[commit-bot: I haz the power, 2015-01-23 16:05:50]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=188893