Fix 2 threading-related bugs in pyauto's remote inspector module.

Fix 2 threading-related bugs in pyauto's remote inspector module.

The first problem was a small typo where the wrong variable was being used (a boolean
value was being used where a threading.Condition object should have been used).

The second problem was in the API functions StartTimelineEventMonitoring and
StopTimelineEventMonitoring.  Previously, these two functions would send a
request to tell the remote inspector to start/stop timeline mode, but they did
not wait until the requests were serviced before returning.  This sometimes led
to subtle multithreading problems where the remote inspector module would hang.
The fix is to ensure these two API functions wait until their requests are
serviced before returning.

BUG=None
TEST=Ran a Chrome Endure test for 5 seconds with --repeat=100.  Previously, we'd see
a hang within the first 10 runs or so.  Now, all 100 runs pass.
NOTRY=true


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=147859

[Nirnimesh, 2012-07-23 07:10:01]

LGTM

[commit-bot: I haz the power, 2012-07-23 16:20:26]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dennisjeffrey@chromium.org/10795055/1

[commit-bot: I haz the power, 2012-07-23 16:20:55]

Change committed as 147859