Fix runtest --path for tests built against SDK.

Bug 4556556

Change-Id: I3f829cae8f9fc1e64b3a44ac9e306b13b3cead7c
diff --git a/testrunner/test_defs/test_walker.py b/testrunner/test_defs/test_walker.py
index de93c80..2989125 100755
--- a/testrunner/test_defs/test_walker.py
+++ b/testrunner/test_defs/test_walker.py
@@ -191,7 +191,7 @@
     """
     if android_mk_parser.HasGTest():
       return gtest.GTestFactory(path, upstream_build_path=upstream_build_path)
-    elif android_mk_parser.HasJavaLibrary('android.test.runner'):
+    elif instrumentation_test.HasInstrumentationTest(path):
       return instrumentation_test.InstrumentationTestFactory(path,
           upstream_build_path=upstream_build_path)
     else: