Update unit tests to build into /data/bin

Tradefed needs these tests to be in the /DATA directory.

Test: cd vendor/widevine && ./build_and_run_all_unit_tests
      All tests should build and pass.
      make tests
      unzip android-tests.zip and verify all tests located in DATA/bin

Bug: 62055647
Change-Id: I35925e29558561c4726bb2249499bfee4e54cf45

libwvdrmengine/test/java/Android.mk

@@ -11,6 +11,9 @@ LOCAL_JAVA_LIBRARIES := org.apache.http.legacy
 
 LOCAL_DEX_PREOPT := false
 
+# When built, explicitly put it in the data/app partition.
+LOCAL_MODULE_PATH := $(TARGET_OUT_DATA_APPS)
+
 # TODO: This test app depends on framework implementation details.
 # LOCAL_SDK_VERSION := current