track pkgname/version in media.metrics

Enhances the media.metrics subsystem to track the pkg name & version
so analysis can move from "error rate has climbed" to "error rate has
climbed within app X".

Changes include fields to hold package name/version, the dump protocol
to emit those fields to upload, and better management of metrics data on
device (time and quantity).

Bug: 65027506
Test: review output of dumpsys media.metrics
Change-Id: Ia55b859d903835c84f7d43883f959dc1cdefb081