Fix IO thread hang on releasing a socket.

net/socket/tcp_client_socket_pool_unittest.cc

Index: net/socket/tcp_client_socket_pool_unittest.cc
diff --git a/net/socket/tcp_client_socket_pool_unittest.cc b/net/socket/tcp_client_socket_pool_unittest.cc
index 6df566babe07c52ec37acc37f9092ba558b7a5ad..cba12b507d2955e882dfbeda51e014d41921bbd7 100644
--- a/net/socket/tcp_client_socket_pool_unittest.cc
+++ b/net/socket/tcp_client_socket_pool_unittest.cc
@@ -731,6 +731,13 @@ TEST_F(TCPClientSocketPoolTest, BackupSocketConnect) {
     // One socket is stalled, the other is active.
     EXPECT_EQ(0, pool_->IdleSocketCount());
     handle.Reset();
+
+    pool_ = new TCPClientSocketPool(kMaxSockets,
+                                    kMaxSocketsPerGroup,
+                                    "TCPUnitTest",
+                                    host_resolver_,
+                                    &client_socket_factory_,
+                                    NULL);
   }
 }