Fixed hanging scripts trying to parse stderr

code.py, specifically, was getting messed up by inconsequential GCC
objdump errors on Clang -g3 generated binaries.

Now stderr from child processes is just redirected to /dev/null when
-v/--verbose is not provided.

If we actually depended on redirecting stderr->stdout these scripts
would have been broken when -v/--verbose was provided anyways. Not
really sure what the original code was trying to do...

scripts/test.py

@@ -670,7 +670,7 @@ def find_perms(runner, test_ids=[], **args):
         print(' '.join(shlex.quote(c) for c in cmd))
     proc = sp.Popen(cmd,
         stdout=sp.PIPE,
-        stderr=sp.PIPE if not args.get('verbose') else None,
+        stderr=None if args.get('verbose') else sp.DEVNULL,
         universal_newlines=True,
         errors='replace',
         close_fds=False)
@@ -702,7 +702,7 @@ def find_perms(runner, test_ids=[], **args):
         print(' '.join(shlex.quote(c) for c in cmd))
     proc = sp.Popen(cmd,
         stdout=sp.PIPE,
-        stderr=sp.PIPE if not args.get('verbose') else None,
+        stderr=None if args.get('verbose') else sp.DEVNULL,
         universal_newlines=True,
         errors='replace',
         close_fds=False)
@@ -749,7 +749,7 @@ def find_path(runner, id, **args):
         print(' '.join(shlex.quote(c) for c in cmd))
     proc = sp.Popen(cmd,
         stdout=sp.PIPE,
-        stderr=sp.PIPE if not args.get('verbose') else None,
+        stderr=None if args.get('verbose') else sp.DEVNULL,
         universal_newlines=True,
         errors='replace',
         close_fds=False)
@@ -780,7 +780,7 @@ def find_defines(runner, id, **args):
         print(' '.join(shlex.quote(c) for c in cmd))
     proc = sp.Popen(cmd,
         stdout=sp.PIPE,
-        stderr=sp.PIPE if not args.get('verbose') else None,
+        stderr=None if args.get('verbose') else sp.DEVNULL,
         universal_newlines=True,
         errors='replace',
         close_fds=False)