[vold] Add argument verification to IncFS methods

+ Get rid of an extra string copy in path validation function

Bug: 152349257
Test: atest vold_tests
Change-Id: I03a8cab0dd6abd7d5c9dcbbc2acb651e818e6cd8
diff --git a/tests/Android.bp b/tests/Android.bp
index 4731d0a..b90de3a 100644
--- a/tests/Android.bp
+++ b/tests/Android.bp
@@ -7,7 +7,9 @@
 
     srcs: [
         "Utils_test.cpp",
+        "VoldNativeServiceValidation_test.cpp",
         "cryptfs_test.cpp",
     ],
     static_libs: ["libvold"],
+    shared_libs: ["libbinder"]
 }