Remove legacy bugreport flow code

* Remove USE_BUGREPORT_API check that enabled us to switch between
  legacy bugreport flow and API workflow.
* Undeprecate requestBugReport flavors as these will not be deprecated.
  Initially it was aimed to remove these methods and use the API
  directly. But now these methods have all been migrated to
  use bugreport API.
* Add @BugreportParams annotation for requestBugReport function.
* Title and Description are communicated via the broadcast instead of
  setting system properties.
* Description is not a system property anymore, so add a check on its
  length by defining MAX_BUGREPORT_DESCRIPTION_SIZE.

Bug: 137825297
Test: Takes interactive and full bugreport as expected
Change-Id: Ib96ad774f5e21491c0dad82cb2292960aa45d6d0