Implements CPU measurement of a WebRTC call on Mac.

Implements CPU measurement of a WebRTC call on Mac.

There's special Mach port magic required to measure CPU on a process other than the current process. Since we want to measure both the renderer and browser process CPU we need to do this.

BUG=

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=222045

[phoglund_chromium, 2013-09-06 07:19:09]

jam, tommi, please have a look.

I needed to hack a DEPS file to get this done, which doesn't seem like a very
good solution. Do you have any suggestions on how to be able to measure on both
the browser and renderer processes? Perhaps I should implement a separate test
in content_browsertests for the measurement on the renderer process, since
content_browsertests should be able to access mach_broker_mac.h directly?

[tommi (sloooow) - chröme, 2013-09-06 07:45:05]

Yes I think moving to content would be the right thing to do.

[phoglund_chromium, 2013-09-06 09:02:45]

Ok, I put in a stopgap for now which will report incorrect values for mac, and
then I will move all renderer process measurement to content browser tests in a
later patch.

[tommi (sloooow) - chröme, 2013-09-06 11:22:04]

sgtm lgtm

[jam, 2013-09-06 16:24:15]

(removing myself as a reviewer since tommi is an owner)

[commit-bot: I haz the power, 2013-09-09 11:10:25]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/phoglund@chromium.org/24024003/7001

[commit-bot: I haz the power, 2013-09-09 16:47:21]

Change committed as 222045