Fix Linux panels to return to minimized mode after mouse moves away.

Fix Linux panels to return to fully minimized mode after mouse moves away.

Regression came from change to leave panel in title-only mode
when draw attention is cleared, but mouse is over the panel title. (r137530)

BUG=None
TEST=Updated StopDrawingAttentionWhileMinimized and DragMinimizedPanelWhileDrawingAttention


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=151190

[jennb, 2012-08-09 00:32:46]

The panels were staying in hover mode because we keep posting a new task to
bring down the panels before the previous task has a chance to run. The new task
cancels previously posted tasks. The guard in BringUpOrDownTitlebars was removed
to get the StopDrawingAttentionWhileMinimized test to pass, but I think the test
did not realistically simulate typical usage scenarios. I put the guard back and
updated the test instead.

[jennb, 2012-08-10 03:46:56]

Jian - pinging to make sure you saw this patch, too.

[jianli, 2012-08-10 16:53:16]

lgtm

[commit-bot: I haz the power, 2012-08-10 17:48:27]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/jennb@chromium.org/10828220/7002

[commit-bot: I haz the power, 2012-08-10 18:27:17]

Try job failure for 10828220-7002 (retry) on linux_clang for step "update"
(clobber build).
It's a second try, previously, step "compile" failed.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=linux_clan...

Step "update" is always a major failure.
Look at the try server FAQ for more details.

[commit-bot: I haz the power, 2012-08-11 03:44:02]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/jennb@chromium.org/10828220/7002

[commit-bot: I haz the power, 2012-08-12 01:56:54]

Change committed as 151190