[Mac] Temporarily disable timer coalescing

[Mac] Temporarily disable timer coalescing on Mac.

In the interest of conserving power, several incremental changes to timer slack have been committed over the last few weeks.  This CL disables those changes so we can get some numbers for the combined effect in terms of power usage and idle wakeup numbers.

This needs to be checked in because we can only get a good comparative measure for this when run on the bots in a controlled environment.

BUG=356804
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=283311

[Mark Mentovai, 2014-07-15 13:50:35]

https://codereview.chromium.org/395763002/diff/20001/base/message_loop/messag...
File base/message_loop/message_pump_mac.mm (left):

https://codereview.chromium.org/395763002/diff/20001/base/message_loop/messag...
base/message_loop/message_pump_mac.mm:74: void
SetTimerTolerance(CFRunLoopTimerRef timer, CFTimeInterval tolerance) {
This will be less work to review when you re-land if instead of removing it and
reintroducing it wholesale, you left this function intact and disabled its body
with #if 0. Then you could also leave the calls to this function, below, intact.

[jeremy, 2014-07-15 13:58:22]

Makes sense, done.

[Mark Mentovai, 2014-07-15 14:03:35]

LGTM

[jeremy, 2014-07-15 14:04:14]

The CQ bit was checked by jeremy@chromium.org

[commit-bot: I haz the power, 2014-07-15 14:06:53]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jeremy@chromium.org/395763002/40001

[commit-bot: I haz the power, 2014-07-16 00:59:34]

Change committed as 283311