Avoid using ToInternalValue in computing timings, so that the timings are consistent accross platfo…

Avoid using ToInternalValue in computing timings, so that the timings are consistent accross platforms and with javascript performance timings API.

BUG=413672
Committed: https://crrev.com/8cc4ec76a0588a3f1fbb89f033cf0b919233ac86
Cr-Commit-Position: refs/heads/master@{#295123}

[azarchs, 2014-09-15 11:58:09]

azarchs@chromium.org changed reviewers:
+ jeremy@chromium.org

[azarchs, 2014-09-15 11:58:10]

Hi Jeremy,
Looks like you were the one who last touched at least the part of this in
startup_metric_utils.  If you have a suggestion for a better reviewer please let
me know.

[jeremy, 2014-09-16 11:37:07]

I seem to remember I chose to use ToInternalValue() explicitly rather than a
unix-epoch based measurement but I don't remember why.

Could you verify that this doesn't mess up the benchmark results when you build
chrome then run:
$ tools/perf/run_benchmark startup.cold.blank_page

If the numbers look ok then I guess this is fine.

Thanks for the cleanup, sorry I don't remember this detail :(

https://codereview.chromium.org/557953006/diff/20001/content/renderer/stats_c...
File content/renderer/stats_collection_controller.cc (right):

https://codereview.chromium.org/557953006/diff/20001/content/renderer/stats_c...
content/renderer/stats_collection_controller.cc:50: // load_start_ms is
represented as milliseconds since system boot.
Comment needs updating

[azarchs, 2014-09-16 14:05:56]

Checked on android and the timings still look correct.

https://codereview.chromium.org/557953006/diff/20001/content/renderer/stats_c...
File content/renderer/stats_collection_controller.cc (right):

https://codereview.chromium.org/557953006/diff/20001/content/renderer/stats_c...
content/renderer/stats_collection_controller.cc:50: // load_start_ms is
represented as milliseconds since system boot.
On 2014/09/16 11:37:07, jeremy wrote:
> Comment needs updating

Done.  It was already inaccurite, of course (before it was ms since an arbitrary
epoch; unix for macOS, windows for everything else)

[jeremy, 2014-09-16 15:37:00]

LGTM

[azarchs, 2014-09-16 15:51:11]

The CQ bit was checked by azarchs@chromium.org

[commit-bot: I haz the power, 2014-09-16 15:52:15]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patchset/557953006/40001

[commit-bot: I haz the power, 2014-09-16 16:02:56]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-09-16 16:02:57]

Try jobs failed on following builders:
  chromium_presubmit on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)

[azarchs, 2014-09-16 16:03:06]

azarchs@chromium.org changed reviewers:
+ brettw@chromium.org

[azarchs, 2014-09-16 16:03:07]

+brettw for owners approval.

[brettw, 2014-09-16 17:23:35]

lgtm

[azarchs, 2014-09-16 18:22:43]

The CQ bit was checked by azarchs@chromium.org

[commit-bot: I haz the power, 2014-09-16 18:24:30]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patchset/557953006/40001

[commit-bot: I haz the power, 2014-09-16 19:23:53]

Committed patchset #3 (id:40001) as 8e9d1f83c35cdf0dc4c11354eadfad751c3936f6

[commit-bot: I haz the power, 2014-09-16 19:25:28]

Patchset 3 (id:??) landed as
https://crrev.com/8cc4ec76a0588a3f1fbb89f033cf0b919233ac86
Cr-Commit-Position: refs/heads/master@{#295123}