time: Add a static TimeTicks method that returns the underlying clock
In a follow-up CL, the return value of this method will be written into
traces recorded by Chrome so that, when syncing Chrome traces with
external traces, we have more information to determine whether the two
traces use timestamps from the same underlying clock and can therefore
be combined.
BUG=597350
Review URL: https://codereview.chromium.org/1824673002
Cr-Commit-Position: refs/heads/master@{#384352}
CrOS-Libchrome-Original-Commit: fdd7d49cc24ed079bfe164110970c25723d363a8
2 files changed