[veridex] Reflective usage detection improvements.

- Convert a string name to the internal name
- Recognize ClassLoader.loadClass.
- Do a dummy merge in VeriFlow by just overwriting registers.

bug: 77513322
Test: m

(cherry picked from commit 295cba006e5212c06fde5ec956c81c507b2974e6)

Change-Id: I888ff742197f4aec9aee68a03daca84f165e4114
6 files changed