Add dummy -j flags to pixel and javascript test runners

testing/tools/run_pixel_tests.py

 #!/usr/bin/env python
 # Copyright 2015 The PDFium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import optparse
 import os
 import re
 import subprocess
 import sys
@@ skipping 37 matching lines @@
   if image_differ.HasDifferences(input_filename, source_dir, working_dir):
     print "FAILURE: " + input_filename
     return False
   return True
 
 
 def main():
   parser = optparse.OptionParser()
   parser.add_option('--build-dir', default=os.path.join('out', 'Debug'),
                     help='relative path from the base source directory')
+  parser.add_option('-j', default=1,
+                    dest='num_workers', type='int',
+                    help='run NUM_WORKERS jobs in parallel (currently ignored)')
   parser.add_option('--wrapper', default='', dest="wrapper",
                     help='Dr. Memory wrapper for running test under Dr. Memory')
   options, args = parser.parse_args()
   finder = common.DirectoryFinder(options.build_dir)
   fixup_path = finder.ScriptPath('fixup_pdf_template.py')
   source_dir = finder.TestingDir(os.path.join('resources', 'pixel'))
   pdfium_test_path = finder.ExecutablePath('pdfium_test')
   if not os.path.exists(pdfium_test_path):
     print "FAILURE: Can't find test executable '%s'" % pdfium_test_path
     print "Use --build-dir to specify its location."
@@ skipping 30 matching lines @@
     failures.sort()
     print '\n\nSummary of Failures:'
     for failure in failures:
       print failure
     return 1
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main())