Track OkHttp changes

As part of creating a full facade over OkHttp code there
are some changes to OkHttp-related classes that must be tracked.
See the related external/okhttp commit for details.

Some non-functional lint / WS changes have been made as part of this
change.

Test: Ran CtsLibcoreOkHttpTestCases entirely
Test: Ran CtsLibcoreTestCases entirely
Test: run cts-dev -m CtsNetTestCases -t android.net.http.cts.HttpResponseCacheTest
Bug: 111055375
Change-Id: I0b0ec21fa376ea33e2fa5486e203e92d3c3337cf