Mark failing tests on chromeOnAndroid platform.

Mark failing dart2js_extra isolate test on chromeOnAndroid platform.  Mark two flaky tests with timeouts.

BUG=dartbug.com/14458
R=kustermann@google.com

Committed: https://code.google.com/p/dart/source/detail?r=31096

[kustermann, 2013-12-12 13:16:07]

lgtm

Are the same tests timing out or is it every time a different timeout?

As already mentioned, if these timeouts are random, it doesn't help if we update
the status file with "Pass, Timeout". If this is the case, the device probably
goes to standby/sleep mode after a certain amount of time.

[Bill Hesse, 2013-12-12 13:19:19]

On 2013/12/12 13:16:07, kustermann wrote:
> lgtm
> 
> Are the same tests timing out or is it every time a different timeout?
> 
> As already mentioned, if these timeouts are random, it doesn't help if we
update
> the status file with "Pass, Timeout". If this is the case, the device probably
> goes to standby/sleep mode after a certain amount of time.

I'm finding out if these timeouts are random.  Right now i'm suppressing these
two, but I will search the logs for them, and for future ones, to see if they
are completely random.  If so, then we need to find the fundamental problem. 
How would we find out if it is sleep mode?

[Bill Hesse, 2013-12-12 14:24:13]

Committed patchset #3 manually as r31096 (presubmit successful).