Migrate frameworks/base/tests/testables and its users to androidx.test

See go/jetpack-test-android-migration

This is the internal version of AOSP change aosp/908373

Test: m -j TestablesTests NetworkStackTests FrameworksServicesTests SystemUITests FrameworksUiServicesTests ExtServicesUnitTests WmTests FrameworksCoreTests

Exempt-From-Owner-Approval: automated package name refactoring; already reviewed on AOSP
Change-Id: Ib04d80954bd8536914d88c66b28e6632e60a6245
diff --git a/packages/NetworkStack/tests/src/android/net/dhcp/DhcpPacketTest.java b/packages/NetworkStack/tests/src/android/net/dhcp/DhcpPacketTest.java
index 7544e72..4d98403 100644
--- a/packages/NetworkStack/tests/src/android/net/dhcp/DhcpPacketTest.java
+++ b/packages/NetworkStack/tests/src/android/net/dhcp/DhcpPacketTest.java
@@ -48,8 +48,9 @@
 import android.net.LinkAddress;
 import android.net.NetworkUtils;
 import android.net.metrics.DhcpErrorEvent;
-import android.support.test.filters.SmallTest;
-import android.support.test.runner.AndroidJUnit4;
+
+import androidx.test.filters.SmallTest;
+import androidx.test.runner.AndroidJUnit4;
 
 import com.android.internal.util.HexDump;
 
@@ -324,7 +325,7 @@
     @Test
     public void testOffer1() throws Exception {
         // TODO: Turn all of these into golden files. This will probably require using
-        // android.support.test.InstrumentationRegistry for obtaining a Context object
+        // androidx.test.InstrumentationRegistry for obtaining a Context object
         // to read such golden files, along with an appropriate Android.mk.
         final ByteBuffer packet = ByteBuffer.wrap(HexDump.hexStringToByteArray(
             // IP header.