libbinder_ndk: make test work w/ TEST_MAPPING

Since it was broken.

This was two modules, but it's better to make it one (and fork w/
PR_SET_PDEATHSIG so that the test doesn't get into a bad state).

Test: libbinder_ndk_unit_test
Change-Id: I928fe70b401f7c523f664c898f882afe08aec741
diff --git a/libs/binder/TEST_MAPPING b/libs/binder/TEST_MAPPING
index b3afd81..55419eb 100644
--- a/libs/binder/TEST_MAPPING
+++ b/libs/binder/TEST_MAPPING
@@ -19,6 +19,9 @@
       "name": "binderStabilityTest"
     },
     {
+      "name": "libbinder_ndk_unit_test"
+    },
+    {
       "name": "CtsNdkBinderTestCases"
     }
   ]