XDG isn't thread safe. Add a lock around calls to it.

XDG isn't thread safe.  Add a lock around calls to it.

BUG=71586
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=79851

[Tom Sepez, 2011-03-22 00:02:57]

Quick CL to add the locking until the thread "jank" is sorted out.

[Tom Sepez, 2011-03-28 19:16:31]

Evan,

I know you're swamped, but wanted to be sure this didn't fall off your screen. 
Thanks heaps.

[Evan Martin, 2011-03-29 08:43:13]

I coulda sworn we already had this change in place.  Lei, do you remember this?

(Sorry tsepez, I'm in a bad time zone so my review latency is high; Lei knows
more about this stuff than me anyway I think)

[Lei Zhang, 2011-03-29 21:45:15]

On 2011/03/29 08:43:13, Evan Martin wrote:
> I coulda sworn we already had this change in place.  Lei, do you remember
this?
> 
> (Sorry tsepez, I'm in a bad time zone so my review latency is high; Lei knows
> more about this stuff than me anyway I think)

The changes from r74183 are in the same methods where you are adding the locks.
Are you adding the locks because there are calls to xdg-mime that currently
ignore the thread restrictions?

[Tom Sepez, 2011-03-29 22:17:14]

Asserting IO allowed isn't the same thing as proving that all the calls are
coming from a single thread.  We want this to be safe even when a thread
disobeys the restriction.

[Lei Zhang, 2011-03-29 22:19:49]

LGTM

Ok, sounds like we are on the same page.