Provide chart function labels over the wire instead of making them up
Summary: Ref T13279. Makes charts incrementally more useful by allowing the server to provide labels and colors for functions.
Test Plan: {F6438872}
Reviewers: amckinley
Reviewed By: amckinley
Subscribers: yelirekim
Maniphest Tasks: T13279
Differential Revision: https://secure.phabricator.com/D20501