Add support for Telecom analytics extensions

Add classes for call events and a field for them in
ParcelableCallAnalytics.
Add classes for timing information on user-visible operations.
Add the TelecomAnalytics class as the top-level object for analytics.
Add log session timing information to the TelecomAnalytics class,
independent of individual calls.

Bug: 28623064
Change-Id: Ifee5fdf6b6b341869ff0ff26c4388d357e3d9922