Add support for logging complex events from C++.

Also include relevant new metric_logger.proto values.

Test: m
Test: Exercised by ag/3890335 in art
Bug: 77517571
Merged-In: Ia527f2b94c7a6147ad9d537376266e5ffc597b04
Change-Id: Ia527f2b94c7a6147ad9d537376266e5ffc597b04
(cherry picked from commit d0613ac5)