tree e191f6513b7a36f21f74ea13947e27974846d033
parent ea4ccd42eb5f3827d760d70ac79335c9e666e0d7
author twerth <twerth@google.com> 1554995640 -0700
committer Copybara-Service <copybara-worker@google.com> 1554995703 -0700

Add option to add metadata to the JSON profile.

This will currently add the build ID, the output base and a date. This data is
accessible by clicking on the button labeled with 'M' in the Chrome Trace
Viewer.

The side effect is that the format of the profile changes from JSON array to
JSON object. See
https://docs.google.com/document/d/1CvAClvFfyA5R-PhYUmn5OOQtYMH4h6I0nSsKchNAySU/preview#

RELNOTES: None
PiperOrigin-RevId: 243071398