Move most of appops service code back into main class
This is effectively a revert of 313162bf and 8fb6ff27
Test: atest -p
frameworks/base/services/core/java/com/android/server/appop
Bug: 256730492
Fixes: 261186662
Fixes: 261155210
Change-Id: If328baaca57f846455f9592a76d2c7a1cf8f5ee6