When an idle socket is added back to a socket pool,
check if lower layer socket pools are stalled.  If so,
close the idle socket.

Also, when a SPDY stream is destroyed, check if
the session is idle and a lower layer pool is stalled,
and close the session if needed.

BUG=92244

Review URL: https://chromiumcodereview.appspot.com/18796003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@219147 0039d316-1c4b-4281-b951-d872f2087c98
18 files changed