...following feedback

Test: FrameworksNetTests
Change-Id: I9c25f0b066a58980bf071d2b958223ed609f0d8e

Avoid network agents trying to do things that the stack
does not support.

Test: new test in this change
Change-Id: I3ffa1c3ddbb0b648b06862dc0a44f8525d358acc

This can only run where the connectivity module is updated

Bug: 308601625
Test: TH
Change-Id: Icc5df3013e90070502a805abe89725591470b464

Test: m checkapi in udc-mainlnine branch
Change-Id: I9baa1b1537b4ceb1ac9696da2026fffd71c58067

Test: atest ConnectivityCoverageTests:android.net.connectivity.com.android.server.net.NetworkStatsServiceTest
     (with debug code that dump all threads at the end of tests)
Fix: 308544001
Change-Id: I597054633bbb008ffd0edebe34dcf6935958aa5d

* changes:
  Add Log.wtf when keepalive metrics are unexpected.
  Add dump of KeepaliveStatsTracker

To debug unexpected keepalive metrics values, print the built
metrics in a Log.wtf before writing it to statsd.

Bug: 297292877
Test: atest FrameworksNetTests
Change-Id: I5fffc13721e50e28f24b0da12a961364f3f77e21

To debug unexpected metrics values, print the built metrics into
the connectivity dump.

Sample of the added log dump:
KeepaliveStatsTracker enabled: true
   # android.net.connectivity.com.android.metrics.Dailykeepalive
InfoReported@3293424e
   automatic_keepalive_requests: 2
   distinct_user_count: 1
   duration_per_num_of_keepalive {
     duration_for_num_of_keepalive {
       keepalive_active_durations_msec: 36
       keepalive_registered_durations_msec: 36
       num_of_keepalive: 0
     }
     duration_for_num_of_keepalive {
       keepalive_active_durations_msec: 9
       keepalive_registered_durations_msec: 6
       num_of_keepalive: 1
     }
     duration_for_num_of_keepalive {
       keepalive_active_durations_msec: 7
       keepalive_registered_durations_msec: 10
       num_of_keepalive: 2
     }
   }
   keepalive_lifetime_per_carrier {
     keepalive_lifetime_for_carrier {
       active_lifetime_msec: 23
       carrier_id: -1
       intervals_msec: 10000
       lifetime_msec: 26
       transport_types: 1
     }
   }
   keepalive_requests: 2
   uid: 10097

Bug: 297292877
Test: adb shell dumpsys connectivity
Test: New test testDumpDoesNotCrash()
Change-Id: Ifc076a8dce734e9c175f1b1f28e1c448b9a792e5

* changes:
  [Test] for libcom.android.tethering.dns_helper.so
  Add a library for DNS resolver to read bpf maps

This change adds a DataSaverStatusTracker, which is a helper
class to continuously track data saver status through NPMS
public API and intents. ConnectivityManager#isUidNetworkingBlocked
would use this cached information along with bpf maps to decide
whether networking of an uid is blocked.

Test: atest FrameworksNetTests:android.net.connectivity.android.net.BpfNetMapsReaderTest
Test: atest ConnectivityCoverageTests:android.net.connectivity.android.net.ConnectivityManagerTest
Bug: 297836825
Change-Id: I7e13191759430f3ea1f4dec7facc02f16be7146d

The created handler threads should be quit after the tests to
prevent memory leakage. Also, this commit updates the method
used to close the created HandlerThread to do it correctly.

Bug: 308537727
Test: atest ConnectivityCoverageTests
Change-Id: I3715a73a9142418c05f98bc95e275f97161ab3cd

Resolv_integration_test needs the function to toggle Data Saver settings
in BPF map.

Bug: 288340533
Test: atest resolv_integration_test
Change-Id: I1725d3c8c6fc641b855c935d7289a99f78dd5933

Make ADnsHelper_isUidNetworkingBlocked() to reference 'metered'
information and Data Saver related BPF maps to make the final decision.

Bug: 288340533
Test: atest dns_helper_unit_test
Change-Id: I51b1dadd56a8d6fda3f8b18d64740e52b76e1bfe

Enable test in postsubmit.

According to go/test-mapping-slo-guide, the test needs to meet
postsubmit SLO before adding it to presubmit.

Bug: 288340533
Test: run presubmit
Change-Id: Id5fae55fa0cb7c7b15e183bbea66c7a139360d95

Exercise the BpfReader::isUidNetworkingBlocked().

Bug: 288340533
Test: atest dns_helper_unit_test
Change-Id: Icc889a6a9649e991cba222427f9b8d4f5ee3b325

The library provides an init function and an API for DNS resolver to
query whether the application is allowed to send DNS query based on BPF
maps settings.

Bug: 288340533
Test: atest dns_helper_unit_test (with test CL)
Change-Id: Ibfb383bfb074da2104a25aa4f04ebc32b22d11da

When 'set-inactive' command is used, it is possible for the
test app to get into the NEVER bucket as it wouldn't be
recorded as used by the user in some cases.

Bug: 298816567
Test: atest tests/cts/hostside/src/com/android/cts/net/HostsideRestrictBackgroundNetworkTests.java
Change-Id: If2667a07629b38395d0fed99771488d0900caf18

* changes:
  Stop MockVpn from extending Vpn class.
  Remove unused method calls of MockVpn
  Create local NetworkCapabilites for MockVpn.

This is needed for data stall detection mechanism in NetworkStack
to get the information about whether the network is blocked for
a given uid and conditions. Because the API will be called
frequently from NetworkStack to resolve all status for all uids
on the device, the API cannot call into the service which
creates IPC. Instead, the API need to directly access bpf maps
in the user process to retrieve the status. In this case the
user process is the network stack, the access control is provided
by linux file permission and selinux.

Test: atest FrameworksNetTests:android.net.connectivity.android.net.BpfNetMapsReaderTest
Test: atest FrameworksNetTests:android.net.connectivity.android.net.ConnectivityManagerTest
NO_IFTTT=Refactor only change for firewall chains definitions
Bug: 297836825

Change-Id: Iaf983b71ec98cbfe5152dcfade8a3120f938f135

testV4MappedV6Address fails without change in Struct.java

Bug: 295800201
Test: atest ConnectivityCoverageTests
Change-Id: I4a40bc47b051860c6420f211491e2ecd34c1d732

Bug: 295800201
Test: NetworkStaticLibTests
Change-Id: Ia10e7dd14edfabe0edf5c9e12ceae54a1ff88d13

Dns Resolver needs to know whether a network is metered when checking if
DNS requests will be blocked by Data Saver.

Bug: 288340533
Test: atest FrameworksNetTests
Change-Id: Ia5822dc522c766c7815680003c7ba275d15ccaff