GitLab

Add metrics to record the value of latencyHint which can be one of
four values in the following order:

  "interactive"
  "balanced"
  "playback"
  exact

The first three are the values of the AudioContextLatencyCatergory
enum.  The last is for case when an explicit floating-point value
is given.

When the hint is a floating-point value, we record the value in
milliseconds.

Each of these metrics are recorded each time an AudioContext is
created.

Bug: 1156304
Change-Id: I264f6f9a38983bd0e40f42e720cfcf685e7a1cdc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2586047Reviewed-by: Jesse Doherty <jwd@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Hongchan Choi <hongchan@chromium.org>
Commit-Queue: Raymond Toy <rtoy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#836777}