Merge changes from topic 'net-update-mr2-dev-plus-aosp' into nyc-mr2-dev-plus-aosp

* changes:
  DO NOT MERGE: Add IP conn metrics to dumpsys and bug reports
  DO NOT MERGE: Add missing dependency.
  DO NOT MERGE: Show notification for always-on app VPN
  DO NOT MERGE: Implement metered tracking for NetworkStats summary queries.
  DO NOT MERGE: ConnectivityServiceTest: fix testAvoidBadWifiSettings
  DO NOT MERGE: Fix ConnectivityServiceTest testRequestBenchmark
  DO NOT MERGE: Switch over to new "time.android.com" NTP pool.
  DO NOT MERGE: Define API for metering network stats buckets.
  DO NOT MERGE: Refactored NetworkStatsServiceTest to use Mockito instead of EasyMock.
  DO NOT MERGE: Use @Ignore to explicitly disable a @test method.
  DO NOT MERGE: Fixed NetworkStatsServiceTest and converted it to JUnit4.
  DO NOT MERGE: ConnectivityThread: use lazy holder idiom
  DO NOT MERGE: ConnectivityManager: use ConnectivityThread looper
  DO NOT MERGE: ConnectivityManager: a simpler CallbackHandler
  DO NOT MERGE: Indicate the NsdServiceInfo attributes are only filled in for a resolved service.
  DO NOT MERGE: Add a null check for the OnStartTetheringCallback.
  DO NOT MERGE: [CS] Remove timeout event after first available
  DO NOT MERGE: ApfTest: tag tests with @SmallTest or @MediumTest
  DO NOT MERGE: Unbreak TetherInterfaceStateMachineTest.
  DO NOT MERGE: Move the connectivity tests to frameworks/base/tests/net.
  DO NOT MERGE: De-guava BroadcastInterceptingContext and move it to testutils.
  DO NOT MERGE: Move FakeSettingsProvider to a common location.
  DO NOT MERGE: ConnectivityServiceTest: mark flaky test as such
  DO NOT MERGE: Add fuzzing tests to ApfFilter RA processing
  DO NOT MERGE: Support timeouts for requestNetwork() invocations.
  DO NOT MERGE: Silence the obnoxious MTU 0 error message that occur when no MTU is specified for a given network.