Check for registry and extension existence before web_accessible_resources.

Check for registry and extension existence before web_accessible_resources.

BUG=618300
Committed: https://crrev.com/7e87b4385d57cecc692ceb8b581ecf95215950fd
Cr-Commit-Position: refs/heads/master@{#398627}

[nasko, 2016-06-08 18:01:30]

nasko@chromium.org changed reviewers:
+ asargent@chromium.org

[nasko, 2016-06-08 18:01:31]

Hey Antony,
Can you review this CL for me? It adds a couple of missing nullptr checks. I
would like us to also add some test coverage for different
web_accessible_resources cases, but I can't personally do it before the branch
point.
Thanks in advance!
Nasko

[asargent_no_longer_on_chrome, 2016-06-08 18:30:13]

lgtm

https://codereview.chromium.org/2048693004/diff/1/extensions/browser/extensio...
File extensions/browser/extension_navigation_throttle.cc (right):

https://codereview.chromium.org/2048693004/diff/1/extensions/browser/extensio...
extensions/browser/extension_navigation_throttle.cc:82: return
content::NavigationThrottle::BLOCK_REQUEST;
Off the top of my head I can't think of situations where ExtensionRegistry::Get
would return null here - we use the same object for regular and incognito
profiles because of
https://cs.chromium.org/chromium/src/extensions/browser/extension_registry_fa...

Maybe a race condition at shutdown or something?

Anyhow, it problem doesn't hurt to have the check here.

[asargent_no_longer_on_chrome, 2016-06-08 18:30:56]

> Anyhow, it problem doesn't hurt to have the check here.

Ooops, I meant "...it *probably* doesn't hurt..."

[nasko, 2016-06-08 18:34:22]

On 2016/06/08 18:30:56, Antony Sargent wrote:
> > Anyhow, it problem doesn't hurt to have the check here.
> 
> Ooops, I meant "...it *probably* doesn't hurt..."

We do check elsewhere, so I wanted to be consistent:
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/browser/ext....

Thanks!

[nasko, 2016-06-08 18:34:27]

The CQ bit was checked by nasko@chromium.org

[commit-bot: I haz the power, 2016-06-08 18:34:58]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2048693004/1

[commit-bot: I haz the power, 2016-06-08 18:40:52]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-06-08 18:42:25]

Description was changed from

==========
Check for registry and extension existence before web_accessible_resources.

BUG=618300
==========

to

==========
Check for registry and extension existence before web_accessible_resources.

BUG=618300

Committed: https://crrev.com/7e87b4385d57cecc692ceb8b581ecf95215950fd
Cr-Commit-Position: refs/heads/master@{#398627}
==========

[commit-bot: I haz the power, 2016-06-08 18:42:26]

Patchset 1 (id:??) landed as
https://crrev.com/7e87b4385d57cecc692ceb8b581ecf95215950fd
Cr-Commit-Position: refs/heads/master@{#398627}