Convert to androidx.test from android-support-test.

android-support-test has long been deprecated and unsupported,
and it causes problems having both androidx.test and
androiud.support.test included in one binary.

Bug: 172570181
Test: m -j NullHomeTest mediatunertest mediatranscodingtest mediaroutertest mediaframeworktest BluetoothMidiTests
Change-Id: If86f5634beab88db07656f743b19beddd9d77984
diff --git a/media/tests/TunerTest/AndroidTest.xml b/media/tests/TunerTest/AndroidTest.xml
index d9c31f45..c718b15 100644
--- a/media/tests/TunerTest/AndroidTest.xml
+++ b/media/tests/TunerTest/AndroidTest.xml
@@ -12,6 +12,6 @@
     <test class="com.android.tradefed.testtype.AndroidJUnitTest">
         <option name="package" value="com.android.mediatunertest"/>
         <option name="hidden-api-checks" value="false"/>
-        <option name="runner" value="android.support.test.runner.AndroidJUnitRunner"/>
+        <option name="runner" value="androidx.test.runner.AndroidJUnitRunner"/>
     </test>
 </configuration>