Migrate most of core networking tests to junit4

This patch is a batch of mechanical changes to test classes to migrate
away from AndroidTestCase and TestCase.

Bug: 62918393
Test: runtest frameworks-net
Change-Id: I74134609e511f22c4d9ecd65780e981f9ba7ae3f
8 files changed
tree: 0685087e13330f6814299518fd56122c20ab47f8
  1. core/
  2. services/
  3. tests/