Refactor monotonic clock interface and use raw tick values in stopwatch

Refactor monotonic clock interface and use raw tick values in stopwatch

- Split interface to provide direct access to raw clock value and clock frequency.
- Update Stopwatch to use raw clock value and clock frequency instead of microseconds.
- Fix possible initialization race on OSX

R=rmacnak@google.com

Committed: https://github.com/dart-lang/sdk/commit/dd4ef2909893c055f584e1e8aeecd4c093b077e2

[Cutch, 2016-01-05 17:51:31]

Description was changed from

==========
Refactor monotonic clock interface and use raw tick values in stopwatch

BUG=
==========

to

==========
Refactor monotonic clock interface and use raw tick values in stopwatch

- Split interface to provide direct access to raw clock value and clock
frequency.
- Update Stopwatch to use raw clock value and clock frequency instead of
microseconds.
==========

[Cutch, 2016-01-05 17:51:31]

johnmccutchan@google.com changed reviewers:
+ rmacnak@google.com

[Cutch, 2016-01-05 17:52:36]

Description was changed from

==========
Refactor monotonic clock interface and use raw tick values in stopwatch

- Split interface to provide direct access to raw clock value and clock
frequency.
- Update Stopwatch to use raw clock value and clock frequency instead of
microseconds.
==========

to

==========
Refactor monotonic clock interface and use raw tick values in stopwatch

- Split interface to provide direct access to raw clock value and clock
frequency.
- Update Stopwatch to use raw clock value and clock frequency instead of
microseconds.
- Fix possible initialization race on OSX
==========

[rmacnak, 2016-01-05 18:28:52]

lgtm w/c

https://codereview.chromium.org/1563473002/diff/1/runtime/vm/os_macos.cc
File runtime/vm/os_macos.cc (right):

https://codereview.chromium.org/1563473002/diff/1/runtime/vm/os_macos.cc#newc...
runtime/vm/os_macos.cc:112: ASSERT(timebase_info.denom != 0);
Also change the copy in bin/utils_macos.cc

[Cutch, 2016-01-05 19:16:14]

https://codereview.chromium.org/1563473002/diff/1/runtime/vm/os_macos.cc
File runtime/vm/os_macos.cc (right):

https://codereview.chromium.org/1563473002/diff/1/runtime/vm/os_macos.cc#newc...
runtime/vm/os_macos.cc:112: ASSERT(timebase_info.denom != 0);
On 2016/01/05 18:28:52, rmacnak wrote:
> Also change the copy in bin/utils_macos.cc

Done.

[Cutch, 2016-01-05 19:22:24]

Description was changed from

==========
Refactor monotonic clock interface and use raw tick values in stopwatch

- Split interface to provide direct access to raw clock value and clock
frequency.
- Update Stopwatch to use raw clock value and clock frequency instead of
microseconds.
- Fix possible initialization race on OSX
==========

to

==========
Refactor monotonic clock interface and use raw tick values in stopwatch

- Split interface to provide direct access to raw clock value and clock
frequency.
- Update Stopwatch to use raw clock value and clock frequency instead of
microseconds.
- Fix possible initialization race on OSX

R=rmacnak@google.com

Committed:
https://github.com/dart-lang/sdk/commit/dd4ef2909893c055f584e1e8aeecd4c093b077e2
==========

[Cutch, 2016-01-05 19:22:25]

Committed patchset #2 (id:20001) manually as
dd4ef2909893c055f584e1e8aeecd4c093b077e2 (presubmit successful).