[Extensions] Check is_valid() in app bindings

[Extensions] Check is_valid() in app bindings

The AppBindings object can potentially receive an IPC message after it's
been invalided. Check before entering the v8 context.

BUG=610224
Committed: https://crrev.com/c1872b891a46dda7bd25463374cbd305d343ecfc
Cr-Commit-Position: refs/heads/master@{#392367}

[Devlin, 2016-05-09 16:34:56]

rdevlin.cronin@chromium.org changed reviewers:
+ lazyboy@chromium.org

[lazyboy, 2016-05-09 18:08:00]

lgtm

[Devlin, 2016-05-09 18:10:42]

The CQ bit was checked by rdevlin.cronin@chromium.org

[commit-bot: I haz the power, 2016-05-09 18:11:15]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1960173002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1960173002/1

[commit-bot: I haz the power, 2016-05-09 18:22:58]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-05-09 18:24:49]

Description was changed from

==========
[Extensions] Check is_valid() in app bindings

The AppBindings object can potentially receive an IPC message after it's
been invalided. Check before entering the v8 context.

BUG=610224
==========

to

==========
[Extensions] Check is_valid() in app bindings

The AppBindings object can potentially receive an IPC message after it's
been invalided. Check before entering the v8 context.

BUG=610224

Committed: https://crrev.com/c1872b891a46dda7bd25463374cbd305d343ecfc
Cr-Commit-Position: refs/heads/master@{#392367}
==========

[commit-bot: I haz the power, 2016-05-09 18:24:50]

Patchset 1 (id:??) landed as
https://crrev.com/c1872b891a46dda7bd25463374cbd305d343ecfc
Cr-Commit-Position: refs/heads/master@{#392367}