Merge history of opt/net/ethernet

Renamed files/directories:
java/ --> service-t/src/
tests/ --> tests/ethernet/
Android.bp --> (removed)
OWNERS --> (removed)
.gitignore --> (removed)

BUG: 222234190
TEST: TH
Ignore-AOSP-First: Move with history done per-branch
Merged-In: I06e2568e5e01d855783383552d1b0d7732cefbe0
Change-Id: I37afd5815c471479c3679beae06e47b9ea845044