Remove workarounds to use core platform API

Core platform API stubs are now correctly included in module_current and
system_server_current, so workarounds used to use such APIs can be
removed.

OsCompat and InetAddressCompat were only necessary because manually
adding the stubs did not resolve the problem for classes that had
public API stubs, which shadowed the module API stubs.

The manual stubs dependency was already removed in another change. Also
remove the service jar dependency on android_system_server_stubs_current
as it is already included in sdk_version system_server_current.

Bug: 183097033
Test: atest CtsNetTestCases

Original-Change: https://android-review.googlesource.com/1754889
Merged-In: Id448be03b679f832edb24f1b77f471227faf5268
Change-Id: Id448be03b679f832edb24f1b77f471227faf5268
6 files changed