Garbage collect extensions only if there are no pending extension installs that could still be usin…

Garbage collect extensions only if there are no pending extension installs that could still be using the Temp directory.

BUG=161920
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=170149

[Joao da Silva, 2012-11-28 18:08:30]

This fixes a regression introduced in
https://chromiumcodereview.appspot.com/11198067.

That CL moves the extension's temp dir to the <profile>/Extensions/Temp
directory, but that directory is deleted by GarbageCollectExtensions(). So the
garbage collection can break a concurrent CrxInstaller, and this is now always
triggering the bug mentioned in the CL. Some external extension providers do
push extensions as soon as the profile is initialized, and the ExtensionService
triggers the first garbage-collection at the same time.

It's still possible that an install is started right after the garbage-collect
task was posted. That is not an issue though, because the CrxInstaller also
posts to the same loop to Start(), so the collection is done by then.

@jamescook: please review
@aa, @kalman: please have a look as well

[James Cook, 2012-11-28 18:15:29]

LGTM with one optional nit.  Apologies for introducing the regression.

https://codereview.chromium.org/11411227/diff/1/chrome/browser/extensions/ext...
File chrome/browser/extensions/extension_service.cc (right):

https://codereview.chromium.org/11411227/diff/1/chrome/browser/extensions/ext...
chrome/browser/extensions/extension_service.cc:184: static const int
kGarbageCollectRetryDelay = 30;
optional nit: Constants in anonymous namespace don't need to be "static"

[not at google - send to devlin, 2012-11-28 18:25:28]

lgtm

[commit-bot: I haz the power, 2012-11-28 20:39:46]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/joaodasilva@chromium.org/11411227/1

[commit-bot: I haz the power, 2012-11-28 21:19:57]

Sorry for I got bad news for ya.
Compile failed with a clobber build on win.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win&number...
Your code is likely broken or HEAD is junk. Please ensure your
code is not broken then alert the build sheriffs.
Look at the try server FAQ for more details.

[commit-bot: I haz the power, 2012-11-28 21:37:16]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/joaodasilva@chromium.org/11411227/1

[commit-bot: I haz the power, 2012-11-28 22:06:38]

Sorry for I got bad news for ya.
Compile failed with a clobber build on win.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win&number...
Your code is likely broken or HEAD is junk. Please ensure your
code is not broken then alert the build sheriffs.
Look at the try server FAQ for more details.

[commit-bot: I haz the power, 2012-11-28 23:49:10]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/joaodasilva@chromium.org/11411227/1

[commit-bot: I haz the power, 2012-11-29 00:58:33]

Sorry for I got bad news for ya.
Compile failed with a clobber build on win.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win&number...
Your code is likely broken or HEAD is junk. Please ensure your
code is not broken then alert the build sheriffs.
Look at the try server FAQ for more details.

[commit-bot: I haz the power, 2012-11-29 07:48:42]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/joaodasilva@chromium.org/11411227/1

[commit-bot: I haz the power, 2012-11-29 09:24:23]

Change committed as 170149