Substantial cleanup of camera2 HAL, and some initial unit tests

- Clean up const/struct usage in HAL
- Add user pointer to notify callback
- Revamp allocate_stream, now it picks its own ID.
- Much simpler stream interface
- Merged request/reprocess input queues
- Frame queue interface no longer a mirror of request queue
- Added triggers/notifications
- Added default request creation
- Lots of comments

Unit tests added:

- Lots of utility code to speed up test writing
- Basic open/close
- Capturing 1 raw buffer (request input, frame output, buffer output)
- Capturing a burst of 10 raw buffers

Bug: 6243944
Change-Id: I490bd5df81079a44c43d87b02c9a7f7ca251f531
5 files changed