[scudo] Only init RingBuffer when needed. (#85994)

Only attempt to initialize the ring buffer when tracking is enabled.

Updated unit tests, and added a few new unit tests to verify the
RingBuffer is not initialized by default.

Verified that the two maps associated with the RingBuffer are not
created in processes by default.

GitOrigin-RevId: 0dbd804a690720688d8234d8bdaee8f8f4fdcddc
Change-Id: I52058304a671079f549a9e02d34ba97baa3fa92a
2 files changed