Make memunreachable_binder_test suitable for VTS

Link statically against libmemunreachable to avoid runtime
dependency on libmemunreachable.so.
Provide a better error when run as non-root.
Rename the test to MemunreachableBinderTest.
Add comments explaining the test sequence.

Bug: 28275695
Test: memunreachable_binder_test
Change-Id: Iddfba636205b7ca3ad31a6ba2c4e85abadd32d0d
diff --git a/libmemunreachable/Android.bp b/libmemunreachable/Android.bp
index b428dd7..caca377 100644
--- a/libmemunreachable/Android.bp
+++ b/libmemunreachable/Android.bp
@@ -20,7 +20,7 @@
     },
 }
 
-cc_library_shared {
+cc_library {
     name: "libmemunreachable",
     defaults: ["libmemunreachable_defaults"],
     srcs: [
@@ -88,14 +88,14 @@
 cc_test {
     name: "memunreachable_binder_test",
     defaults: ["libmemunreachable_defaults"],
+    test_suites: ["vts"],
     srcs: [
         "tests/Binder_test.cpp",
-        "tests/MemUnreachable_test.cpp",
     ],
+    static_libs: ["libmemunreachable"],
     shared_libs: [
         "libbinder",
         "libhwbinder",
-        "libmemunreachable",
         "libutils",
     ],
 }