Remove useless TestRunner

InstrumentationTestRunner can enumerate the test cases to run without a
special TestRunner.

Change-Id: I5a49413440ef191f28a21034a318d9a9e3f8174b
diff --git a/keystore/tests/AndroidManifest.xml b/keystore/tests/AndroidManifest.xml
index 1a5f065..415442f 100644
--- a/keystore/tests/AndroidManifest.xml
+++ b/keystore/tests/AndroidManifest.xml
@@ -22,7 +22,7 @@
         <uses-library android:name="android.test.runner" />
     </application>
 
-    <instrumentation android:name=".KeyStoreTestRunner"
+    <instrumentation android:name="android.test.InstrumentationTestRunner"
         android:targetPackage="android.security.tests"
         android:label="KeyStore Tests">
     </instrumentation>