Don't increment lazy keep alive count on redirects.

Don't increment lazy keep alive count on redirects.

The ChromeExtensionNetworkDelegate::OnBeforeURLRequest is called for new
requests as well as for redirects. This results in the lazy keep alive
count in extensions to be incremented several times if there is a redirect
but then it is decremented only ones when the request finishes. In consequence
the lazy extension page never shuts down because the count never reaches
zero.

With this commit requests that have been redirected at least once are
ignored when incrementing the keep alive count.

BUG=175279
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=289260

[agl, 2014-08-12 21:30:55]

No idea about this. Will rubber stamp if mpcomplete agrees with it.

[Matt Perry, 2014-08-12 23:27:27]

LGTM

[agl, 2014-08-12 23:29:15]

lgtm

[msimonides, 2014-08-13 06:34:44]

The CQ bit was checked by msimonides@opera.com

[commit-bot: I haz the power, 2014-08-13 06:36:52]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/msimonides@opera.com/464933002/20001

[commit-bot: I haz the power, 2014-08-13 09:12:54]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  linux_chromium_gn_rel on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[commit-bot: I haz the power, 2014-08-13 09:19:56]

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

[commit-bot: I haz the power, 2014-08-13 09:19:57]

Try jobs failed on following builders:
  linux_chromium_gn_rel on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[msimonides, 2014-08-13 09:36:45]

The CQ bit was checked by msimonides@opera.com

[commit-bot: I haz the power, 2014-08-13 09:38:55]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/msimonides@opera.com/464933002/20001

[commit-bot: I haz the power, 2014-08-13 09:44:52]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  linux_chromium_gn_rel on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[commit-bot: I haz the power, 2014-08-13 10:33:28]

Change committed as 289260