NaCl: create a separate namespace for Mojo handles.

mojo/edk/test/BUILD.gn

Index: mojo/edk/test/BUILD.gn
diff --git a/mojo/edk/test/BUILD.gn b/mojo/edk/test/BUILD.gn
index e8f55adfcf760d181c3eb92976894672633c369d..87357082cde3f15729f71f45f979f8a5fd898428 100644
--- a/mojo/edk/test/BUILD.gn
+++ b/mojo/edk/test/BUILD.gn
@@ -90,6 +90,7 @@ group("public_tests") {
     ":mojo_public_system_perftests",
     ":mojo_public_system_unittests",
     ":mojo_public_utility_unittests",
+    ":mojo_system_impl_private_unittests",
   ]
 }
 
@@ -134,3 +135,10 @@ test("mojo_public_utility_unittests") {
     "../../public/cpp/utility/tests",
   ]
 }
+
+test("mojo_system_impl_private_unittests") {
+  deps = [
+    ":run_all_unittests",
+    "../../public/platform/native:system_impl_private_tests",
+  ]
+}