[Extension Toolbar] Don't synthesize actions for policy extensions

[Extension Toolbar] Don't synthesize actions for policy extensions

Policy extensions weren't installed by the user, and frequently cannot be
uninstalled. Similar to component extensions, we shouldn't synthesize actions
for these extensions.

BUG=463939
Committed: https://crrev.com/b3b2462b4e45fb1722b577415bcb62b1e27ce4aa
Cr-Commit-Position: refs/heads/master@{#319669}

[Devlin, 2015-03-05 19:23:43]

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

[Devlin, 2015-03-05 19:23:44]

Another short one for you, Finnur. :)

[Finnur, 2015-03-06 14:37:18]

You do a great job at making me look more productive. :)

LGTM

[Devlin, 2015-03-07 06:50:41]

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

[commit-bot: I haz the power, 2015-03-07 06:52:02]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/977943002/1

[commit-bot: I haz the power, 2015-03-07 08:52:39]

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

[commit-bot: I haz the power, 2015-03-07 08:52:40]

Try jobs failed on following builders:
  mac_chromium_compile_dbg_ng on tryserver.chromium.mac (JOB_TIMED_OUT, no build
URL)
  mac_chromium_rel_ng on tryserver.chromium.mac (JOB_TIMED_OUT, no build URL)
Timed out jobs are not retried to avoid causing additional load on the builders
with large pending queues.

[Devlin, 2015-03-07 16:39:38]

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

[commit-bot: I haz the power, 2015-03-07 16:40:58]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/977943002/1

[commit-bot: I haz the power, 2015-03-07 18:42:05]

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

[commit-bot: I haz the power, 2015-03-07 18:42:05]

Try jobs failed on following builders:
  mac_chromium_compile_dbg_ng on tryserver.chromium.mac (JOB_TIMED_OUT, no build
URL)
  mac_chromium_rel_ng on tryserver.chromium.mac (JOB_TIMED_OUT, no build URL)
Timed out jobs are not retried to avoid causing additional load on the builders
with large pending queues.

[Devlin, 2015-03-09 05:02:45]

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

[commit-bot: I haz the power, 2015-03-09 05:02:57]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/977943002/1

[commit-bot: I haz the power, 2015-03-09 06:35:23]

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

[commit-bot: I haz the power, 2015-03-09 06:35:27]

Failed to apply the patch.

[commit-bot: I haz the power, 2015-03-09 06:35:36]

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

[Devlin, 2015-03-09 16:16:24]

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

[Devlin, 2015-03-09 16:16:24]

The patchset sent to the CQ was uploaded after l-g-t-m from finnur@chromium.org
Link to the patchset: https://codereview.chromium.org/977943002/#ps20001 (title:
"Latest master")

[commit-bot: I haz the power, 2015-03-09 16:17:09]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/977943002/20001

[commit-bot: I haz the power, 2015-03-09 17:33:14]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-03-09 17:33:50]

Patchset 2 (id:??) landed as
https://crrev.com/b3b2462b4e45fb1722b577415bcb62b1e27ce4aa
Cr-Commit-Position: refs/heads/master@{#319669}