CameraProvider: Refactor legacy name regex code

The match will use iterators that will be invalidated when the
used string input goes out of scope. Refactor the API to return
the two components of the match.

Bug: 36871785
Test: m && m SANITIZE_TARGET=address
Change-Id: I2418541234a09e53856ea61e0fbc4b67d8036308
2 files changed