Fix kotlin nullable errors in net-test-utils and NetworkStaticLibTests

Fix kotlin nullable errors that were exposed by setting the retention
of android.annotation.NonNull and android.annotation.Nullable to
class retention.

Bug: 294110802
Test: builds
Change-Id: I2a2c91188b64619fca190a9bd7812d32f9610abd
diff --git a/staticlibs/tests/unit/src/com/android/net/module/util/CollectionUtilsTest.kt b/staticlibs/tests/unit/src/com/android/net/module/util/CollectionUtilsTest.kt
index 9fb025b..e23f999 100644
--- a/staticlibs/tests/unit/src/com/android/net/module/util/CollectionUtilsTest.kt
+++ b/staticlibs/tests/unit/src/com/android/net/module/util/CollectionUtilsTest.kt
@@ -63,9 +63,6 @@
         assertEquals(0, CollectionUtils.indexOfSubArray(haystack, byteArrayOf()))
         assertEquals(-1, CollectionUtils.indexOfSubArray(byteArrayOf(), byteArrayOf(3, 2)))
         assertEquals(0, CollectionUtils.indexOfSubArray(byteArrayOf(), byteArrayOf()))
-        assertThrows(NullPointerException::class.java) {
-            CollectionUtils.indexOfSubArray(haystack, null)
-        }
     }
 
     @Test
diff --git a/staticlibs/testutils/devicetests/com/android/testutils/FakeDns.kt b/staticlibs/testutils/devicetests/com/android/testutils/FakeDns.kt
index 825d748..1f82a35 100644
--- a/staticlibs/testutils/devicetests/com/android/testutils/FakeDns.kt
+++ b/staticlibs/testutils/devicetests/com/android/testutils/FakeDns.kt
@@ -81,9 +81,9 @@
         var type = if (posType != -1) it.arguments[posType] as Int else TYPE_UNSPECIFIED
         val answer = getAnswer(hostname, type)
 
-        if (!answer?.addresses.isNullOrEmpty()) {
+        if (answer != null && !answer.addresses.isNullOrEmpty()) {
             Handler(Looper.getMainLooper()).post({ executor.execute({
-                    callback.onAnswer(answer?.addresses, 0); }) })
+                    callback.onAnswer(answer.addresses, 0); }) })
         }
     }
 
diff --git a/staticlibs/testutils/devicetests/com/android/testutils/PacketBridge.kt b/staticlibs/testutils/devicetests/com/android/testutils/PacketBridge.kt
index da3508d..d50f78a 100644
--- a/staticlibs/testutils/devicetests/com/android/testutils/PacketBridge.kt
+++ b/staticlibs/testutils/devicetests/com/android/testutils/PacketBridge.kt
@@ -48,8 +48,8 @@
     private val natMap = NatMap()
     private val binder = Binder()
 
-    private val cm = context.getSystemService(ConnectivityManager::class.java)
-    private val tnm = context.getSystemService(TestNetworkManager::class.java)
+    private val cm = context.getSystemService(ConnectivityManager::class.java)!!
+    private val tnm = context.getSystemService(TestNetworkManager::class.java)!!
 
     // Create test networks.
     private val internalIface = tnm.createTunInterface(listOf(internalAddr))
diff --git a/staticlibs/testutils/devicetests/com/android/testutils/TestNetworkTracker.kt b/staticlibs/testutils/devicetests/com/android/testutils/TestNetworkTracker.kt
index b743b6c..84fb47b 100644
--- a/staticlibs/testutils/devicetests/com/android/testutils/TestNetworkTracker.kt
+++ b/staticlibs/testutils/devicetests/com/android/testutils/TestNetworkTracker.kt
@@ -91,7 +91,7 @@
     lp: LinkProperties?,
     setupTimeoutMs: Long = 10_000L
 ): TestNetworkTracker {
-    val tnm = context.getSystemService(TestNetworkManager::class.java)
+    val tnm = context.getSystemService(TestNetworkManager::class.java)!!
     val iface = if (isAtLeastS()) tnm.createTunInterface(linkAddrs)
     else tnm.createTunInterface(linkAddrs.toTypedArray())
     val lpWithIface = if (lp == null) null else LinkProperties(lp).apply {
@@ -112,7 +112,7 @@
     val lp: LinkProperties?,
     setupTimeoutMs: Long
 ) : TestableNetworkCallback.HasNetwork {
-    private val cm = context.getSystemService(ConnectivityManager::class.java)
+    private val cm = context.getSystemService(ConnectivityManager::class.java)!!
     private val binder = Binder()
 
     private val networkCallback: NetworkCallback