Add a regression test for 14056. This verifies that HttpNetworkTransaction se...

Add a regression test for 14056. This verifies that HttpNetworkTransaction sets the "referrer" field expected by the DNS prefetch observer.

BUG=14056
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=18434

[jar (doing other things), 2009-06-15 16:35:37]

If I'm understanding this correctly, then this is a multi-threaded test.  As a
result, it should be possible to get the resolution response before the observer
has been fully notified (if it is potentially run on another thread).  The
hassle is that Murphy threads keep suspending.

Am I understanding the test?... or is it synchronously performed on a single
thread?  ...or perhaps the threads are limited enough that the trick of the next
paragraph is effectively integrated.

If it is multi-threaded, the "trick" to synchronize is to exercise each thread
after you *think* the thread should have gotten the events of interest posted to
it.  Once all the threads have then "exercised," there is no chance for a Murphy
thread to be stuck waiting to do your bidding.

[jar (doing other things), 2009-06-15 18:33:39]

LGTM