Add option to command tester for running a test multiple times. Use that

tools/test_lib.py

Index: tools/test_lib.py
===================================================================
--- tools/test_lib.py	(revision 7086)
+++ tools/test_lib.py	(working copy)
@@ -102,23 +102,6 @@
 def PopenBufSize():
   return 1000 * 1000
 
-def RunCmdWithInput(cmd, input_data):
-  try:
-    sys.stdout.flush() # Make sure stdout stays in sync on the bots.
-    p = subprocess.Popen(cmd,
-                         bufsize=PopenBufSize(),
-                         stdin=subprocess.PIPE)
-    p.communicate(input_data)
-    retcode = p.wait()
-    if retcode != 0:
-      print ('Failed to cmd %s (retcode=%d)' %
-             (cmd, retcode))
-      return False
-  except OSError:
-    print 'RunCmdWithInput exception: ' + str(sys.exc_info()[1])
-    return False
-  return True
-
 def RunTestWithInput(cmd, input_data):
   """Run a test where we only care about the return code."""
   assert type(cmd) == list