Reland 46757.

Reland 46757.
OnAvailableSocketSlot() was dereferencing a NULL pointer.  Add a NULL check.  Add a test.
BUG=42267
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=46837

[willchan no longer on Chromium, 2010-05-10 18:07:17]

http://codereview.chromium.org/2050005/diff/1/2
File net/socket/client_socket_pool_base.cc (right):

http://codereview.chromium.org/2050005/diff/1/2#newcode648
net/socket/client_socket_pool_base.cc:648: (stalled_group_count == 1 &&
top_group->num_releasing_sockets == 0)) {
This is the new check, so we only dereference |top_group| when
|stalled_group_count == 1|.

http://codereview.chromium.org/2050005/diff/1/4
File net/socket/client_socket_pool_base_unittest.cc (right):

http://codereview.chromium.org/2050005/diff/1/4#newcode833
net/socket/client_socket_pool_base_unittest.cc:833:
TEST_F(ClientSocketPoolBaseTest, StallAndThenCancelAndTriggerAvailableSocket) {
This is the new test.

[eroman, 2010-05-10 18:19:16]

ok