This commit adds support of regsitering a service with a custom
hostname. This is required to enable Advertising Proxy feature for Thread
devices.

For example:
```
NsdServiceInfo info = new NsdServiceInfo();

info.setServiceName("My Service");
info.setServiceType("_test._tcp");
info.setHostname("MyHost");
info.setHostAddresses(List.of(address1, address2));

nsdManager.registerService(info, PROTOCOL_DNS_SD, listener);
```

This CL also adds two new error codes for service/host registration
conflict: `FAILURE_SERVICE_NAME_CONFLICT` and
`FAILURE_HOST_NAME_CONFLICT`.

Bug: 284904661
Test: atest CtsNetTestCases FrameworksNetTests

Change-Id: I2fb974c38d851ba99144a18c7047084bbd61b938

setEnabled API is added to ThreadNetworkController, this
can be used by applications with privileged permission to set
Thread to enable/disabled state.

The Thread enabled state can be subscribed with
ThreadNetworkController#registerStateCallback.

When Thread is disabled, the join/scheduleMigration APIs will
fail with ERROR_THREAD_DISABLED.

When Thread is disabling, all commands will fail with ERROR_BUSY.

Bug: 299243765

Test: atest CtsThreadNetworkTestCases:android.net.thread.cts.ThreadNetworkControllerTest

Change-Id: Ifa7845bf1d5664ecd31ce74e24b3a839f92bba13

This commit adds support of discovering services with explicit subtype.

With this change, a service can be discovered with subtype with:
```
nsdManager.discoverServices(
        new DiscoveryRequest.Builder("_http._tcp", PROTOCOL_DNS_SD)
	        .setSubtype("_printer").build(),
	executor, listener);
```

Bug: 265095929
Test: atest CtsNetTestCases FrameworksNetTests
Change-Id: Iba76283a003cf2d52a8c26e1de872c3e8e433350

java_sdk_library modules should specify the aconfig_declarations modules
in order to generate the exportable stubs (i.e. the stubs that exclude
the disabled aconfig flags) by providing the information about the
aconfig flag values.

The exportable stubs will be used when generating the module sdk
snapshots and to generate the hiddenapi flags, in order to prevent
exposing the disabled apis in runtime.

Test: m framework-connectivity-t
Bug: 317290555
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:60b21f877f88a6848ee6d0f0e5316362714b9d25)
Merged-In: Ieb8f41921054ed6f62db2edfc7d695ba0a2a0055
Change-Id: Ieb8f41921054ed6f62db2edfc7d695ba0a2a0055

Some callers of openSessionInternal could have null package name.
Update nullability annotations accordingly.

Test: TH
Bug: N/A
Change-Id: Ifafafcd64612c99e5174364a010ec95415702b0d

This is per the go/android-api-guidelines#return-error:
```
Make sure your chosen error handling option gives you the
flexibility to introduce new error types in the future. For
@IntDef, that means including an OTHER or UNKNOWN value - when
returning a new code, you can check the caller's targetSdkVersion
to avoid returning an error code the application doesn't know
about. For exceptions, have a common superclass that your
exceptions implement, so that any code that handles that type will
also catch and handle subtypes.
```

Bug: 320403080
Change-Id: I2ee663b75107dac6d84fa697f449fa0424128fde

NsdService switched from Netd native solution to Java solution on
Android U. MDNS service provided by Netd will be removed from Android V.

1. Stop registering native mdns service from V.
2. Stop startDaemon() in NsdManager from V.
3. As a double safety, return early in NsdService methods that call the
   native mdns service when platform version is V+.
4. Modify NsdManagerTest to cover V+ behavior.

Bug: 298594687
Test: Build. Presubmit.
Change-Id: Ifdac8f7a44aa57d93d453ba482ec473a2b531452

FastDataInput for reading persistent data is currently disabled
by default. This functionality will be gradually enabled through
A/B experiments to assess its impact.

One-shot boot time increase up to 10 second is one expected
outcome in worst case. Currently, the persistent data was loaded
when the first caller query it, but in this change it will be
done twice in the boot stage due to the needs of doing comparison.

Test: adb shell dumpsys netstats
Test: atest ConnectivityCoverageTests:android.net.connectivity.com.android.server.net.NetworkStatsServiceTest
Test: manual test against data points under benchmark/assets/dataset
Bug: 313841499

Change-Id: Ia927bd115de5453ca3ee22104f3efbf44a55c2b8

This implements a basic border routing test case (ping) and demonstrates a
valid test environment for Thread Border Router test cases.

Later we can add more packet verifications and more test cases.

Bug: 295843010
Test: atest android.net.ThreadBorderRouterTest

Change-Id: Ifb9b6d45539143a227c2bc0ed69b5c3167ef9acd

This commit builds upon CL aosp/2817455 by adding a new NsdManager API to
update registered services directly, eliminating the need for exit and
re-announcement messages. This preserves compatibility with existing
apps without requiring an API bump. If an app registers a service with
the same listener and NsdServiceInfo, it's treated as an update request.

Bug: 309372239
Test: TH
Change-Id: Ib84ddf0d92e757eaef225f3e32f5223bc50c8fd6

This increased reading performance by 35% while running
benchmark tests. But the feature is not enabled in the production
code until the service turns it on.

Test: atest ConnectivityBenchmarkTests
Test: atest ConnectivityCoverageTests:android.net.connectivity.android.net.NetworkStatsCollectionTest
Bug: 313841499

Change-Id: Ic827e6c4848cc31d46d62aa93993b483114a1f12

This is the servide-side impl of the subtypes advertising added in
aosp/2608627. See that CL for more backgrounds.

Bug: 265095929
Test: atest CtsNetTestCases FrameworksNetTests
Change-Id: I3d6f96822ac89d12fe29c00f688d848297c25787

This commit adds support of advertising and discovering services
with subtypes.

With this change, client can publish a new service with subtypes with
code:
```
NsdServiceInfo info = new NsdServiceInfo();
info.setServiceName("My Service");
info.setServiceType("_meshcop._udp");
info.setSubtypes(Set.of("_abc"));

nsdManager.registerService(info, PROTOCOL_DNS_SD, listener);
```

Bug: 265095929
Test: atest CtsNetTestCases FrameworksNetTests
Change-Id: Ia83182e2d43002243d1ef4357d14a8056d7da14b

Bug: 308011229
Test: make update-api
Change-Id: I5ca6278305f814dbce6a7c41a4f4e491b1389b31

This reverts commit 69eb8325.

Bug: 308011229
Change-Id: I4dd68bdedc0088860895a833f2b4cb8e1845429a
Test: IpSecServiceParameterizedTest (new tests)

This reverts commit ab5006c1.

Reason for revert: b/316010034 breaking VCN unit tests

Change-Id: I68cb1a99bb6e492c16901972d201761cd00df6fa

Bug: 308011229
Test: IpSecServiceParameterizedTest (new tests)
Change-Id: I3f1c2ef60ee9b6ac17909e0ee083ee6f8483588e

This is a no-op refactoring to move the ultility method to a
common place to be referenced outside NetworkStatsService
in later patches.

Test: atest ConnectivityCoverageTests:android.net.connectivity.com.android.server.net.NetworkStatsServiceTest
Bug: 313841499
Change-Id: Ib0ef40d87486bf3d8d5b3f97c77291a00c0378ac

Test: TH
Change-Id: Icd3c87a7da9b45e5341a1a2ead68f0a9809591bb

These APIs were released via SDK extension but they need to have
FlaggedAPI annotation to avoid being released by quarterly release.

Note that this CL does not contain udc-extended-api change.
Once com.android.net.flags.register_nsd_offload_engine_api is marked as
released API, APIs with this annotations should be visible in
udc-mainline-prod API .txt files.

Bug: 301713539
Test: TH
Change-Id: I32b58ec64c1f599f48bc89b189ed24ac1717a1d7

The NsdManager constructor creates a new thread, which is not
intended to be closed. However, the test in NsdMangerTest and
NsdServiceTest create a new NsdManager instance, resulting in a
large number of threads running during the tests. This can lead
to an out-of-memory error for the tests. To resolve this issue,
use the common singleton thread ConnectivityThread to handle
tasks from the various instances.

Fix: 308544734
Test: atest ConnectivityCoverageTests --test-filter Nsd*
Change-Id: I1908a2bb1bd20da8e0498353bca26f7e89e16626

MDNS native support from Netd is stopped in V.

Bug: 298594687
Bug: 312092770
Test: run CtsNetTestCasesMaxTargetSdk30 on V, no fatal exception.
Change-Id: I3774288cdf5b82e6aeeee7ee2d030fdc524e1aa8

Test: atest FrameworksNetTests CtsNetTestCases
Bug: 307217169

Change-Id: I006e3191a8c6100af3d2906d5d37f4e38a3db519

Per API council review suggestions in b/309952666, add the same
permission requirements for the unregister APIs.

Bug: 309952666
Test: atest CtsThreadNetworkTestCases
Change-Id: Idc481c7676ddc5d748fe7803f74dd63981186c09

This commit renames `createRandomDataset` to `createRandomizedDataset`
and moves this method to ThreadNetworkController class.

The reason for moving this method is that we rely on the service side to
know which channels are currently supported by this device and there is
no safe way for ActiveOperationalDataset to created a randomized full
dataset by its own. Moving this method to ThreadNetworkController also
allows us to support future platform-dependend configurations.

Bug: 308117328
Bug: 307939803
Change-Id: I0b0b7b727c3b326ab59bb1299ace15df1ff1ad5e

Similar to the Neary and RemoteAuth team, the Thread team will need to update the API files.

Change-Id: I488aae7610e337f14df01f1c6f51f042f11bd450

The ThreadNetworkController class provides APIs for managing the Thread
network, for example, attach to a specific network, form a network with
given dataset or update/migrate an existing network.

Bug: 262683651
Test: atest CtsThreadNetworkTestCases
Change-Id: Ib3c267d2c81a8c3c7772ed3c9cd2092487cc941a

java_sdk_library has previously internally disabled a few legitimate
issues. As this is being un-done for modules, add baselines for the
pre-existing issues.

Bug: 306806877
Test: m checkapi
Merged-In: Ie764d33196675e1482f30ecfd3d6d22b7fa25c27
Change-Id: Ie764d33196675e1482f30ecfd3d6d22b7fa25c27

Bug: 297362755
Test: m checkapi
Merged-In: I25ad2cb4472e52297a455256b5749a90f31ca6b9
Change-Id: I25ad2cb4472e52297a455256b5749a90f31ca6b9

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

Per the API review council, the classes should be "final" by default

Bug: 301076593
Test: build && atest CtsThreadNetworkTestCases
Change-Id: I85f0b4fabe5b1bcec2be052620b38a07c58181d7

Design doc: go/thread-android-api
Android FR: b/235016403

Bug: 262683651
Change-Id: Icbd4ee4150e3fd78df627c2e726c259e7ee50871

This commit declares the initial "thread_enabled" feature flag and use
this to flag all existing and future Thread system APIs with @FlaggedApi

Bug: 301473012
Test: build
Change-Id: I43f64ce38f7fd0806733b21c4f393e4563e6a467

EthernetManager is @SystemApi, so cannot be referenced from public
API.

Bug: 303184203
Test: m docs
Change-Id: Ib5cc07c89b4ecfdeae704da131ebb307816e35fa

This change adds overriding methods that are essential to compile the
stubs generated from the signature files.

More information and the background for this change is available at
go/add-overriding-one-pager.

Test: m checkapi
Bug: 299366704
Change-Id: Idba307148fd9afa87bfb7e0c89e00d9bd97ec204

Currently, metalava will discard concrete overrides of abstract methods
from the API signature files which causes problems when attempting to
generate stubs from those files and also discards information that may
be important in API reviews. This change is the first step in the
process of changing that behavior.

This change hard codes the current behavior for discarding the concrete
overrides (`add-additional-overrides=no`) into those signature files
that will (or are likely) to be affected by the change in behavior.
That allows the default behavior to be changed for all the other files
without affecting these.

Follow up changes will remove the hard coding from the signature files
and will update the contents which will include the concrete overrides
of the abstract methods.

More information and the background for this change is available at
go/add-overriding-one-pager.

Test: m checkapi
Bug: 299366704
Change-Id: I52c5bbe2e3bbd36019fe44fcb0b2d19876a5a869

Change-Id: I7912bf91841a4260d0a1eec022a6a832b312321d

Change-Id: Iad7d1818d1959024d5fd1fc8810d2b7ce0f06e40

Limit the amount of parked code built into Connectivity module

Test: built successfully.
Bug: 300522527
Change-Id: I87d7516011c469aa89fc7e67cf03c4ee8aa1bb9b

This commit sets up the initial Thread network service for the
Android Thread feature which allows an Android device to create
a Thread network and being a Border Router.

See https://www.threadgroup.org/What-is-Thread for background of
Thread.

See b/235016403 for the Android Thread feature request.

Test: lunch aosp_cf_x86_64_tv-userdebug
      m && launch_cvd
      atest CtsThreadNetworkTestCases
Bug: 262683651
Change-Id: Ie1bb23084531f67165ec068ea3ca39592dbc01d1