The coverage tests will allow measuring code coverage for all
Connectivity+Tethering code.

This is a combination of the current TetheringCoverageTests, and
FrameworksNetTests.

Adding min_sdk_version to the test prevents it from using deprecated
IoUtils utilities. Replace it with the non-deprecated alternative.

Bug: 187935317
Test: atest ConnectivityCoverageTests
Original-Change: https://android-review.googlesource.com/1731232
Merged-In: I5366e1cc9cd6ddb41f24718246381cc2b1cc1383
Change-Id: I5366e1cc9cd6ddb41f24718246381cc2b1cc1383