Add Alexei as an OWNER for //base/metrics

BUG=none
TEST=none
R=asvitkine@chromium.org, jar@chromium.org

Review URL: https://codereview.chromium.org/196213002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@256587 0039d316-1c4b-4281-b951-d872f2087c98
[telemetry] Add d3 and some simple viz widgets

This adds some very simple viz widgets. This shows d3 primitives but expressed using the tvcm way of writing components: updating is more explicit, and the public properties on the component cause re-rendering. Subclassing is used for extensibility.

BUG=340096

Review URL: https://codereview.chromium.org/190413002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@256588 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 256588