Add prerequisite dependencies to make ios_test work build on bazel.

--
MOS_MIGRATED_REVID=104673050
diff --git a/tools/objc/BUILD b/tools/objc/BUILD
index 7f87137..1e2875c 100644
--- a/tools/objc/BUILD
+++ b/tools/objc/BUILD
@@ -47,11 +47,12 @@
 
 filegroup(
     name = "srcs",
-    srcs = glob(["**"]),
+    srcs = glob(["**"]) + ["//tools/objc/sim_devices:BUILD"],
 )
 
 filegroup(
     name = "testrunner",
+    srcs = [":testrunner_stub"],
 )
 
 sh_binary(