Flush stdout before launching sub-processes.

testing/tools/run_javascript_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
 
 # Nomenclature:
 #   x_root - "x"
 #   x_filename - "x.ext"
 #   x_path - "path/to/a/b/c/x.ext"
 #   c_dir - "path/to/a/b/c"
 
 def generate_and_test(input_filename, source_dir, working_dir,
                       fixup_path, pdfium_test_path):
   input_root, _ = os.path.splitext(input_filename)
   input_path = os.path.join(source_dir, input_root + '.in')
   pdf_path = os.path.join(working_dir, input_root + '.pdf')
   txt_path = os.path.join(working_dir, input_root + '.txt')
   expected_path = os.path.join(source_dir, input_root + '_expected.txt')
   try:
+    sys.stdout.flush()
     subprocess.check_call(
         [fixup_path, '--output-dir=' + working_dir, input_path])
     with open(txt_path, 'w') as outfile:
       subprocess.check_call([pdfium_test_path, pdf_path], stdout=outfile)
     subprocess.check_call(['diff', expected_path, txt_path])
   except subprocess.CalledProcessError as e:
     print "FAILURE: " + input_filename + "; " + str(e)
     return False
   return True
 
@@ skipping 37 matching lines @@
   if sys.platform.startswith('win'):
     pdfium_test_path = pdfium_test_path + '.exe'
   # TODO(tsepez): Mac may require special handling here.
 
   # Place generated files under the build directory, not source directory.
   gen_dir = os.path.join(build_dir, 'gen', 'pdfium')
   working_dir = os.path.join(gen_dir, 'testing', 'javascript')
   if not os.path.exists(working_dir):
     os.makedirs(working_dir)
 
-  os_exit_code = 0
+  failures = []
   input_file_re = re.compile('^[a-zA-Z0-9_.]+[.]in$')
   for input_filename in os.listdir(source_dir):
     if input_file_re.match(input_filename):
       input_path = os.path.join(source_dir, input_filename)
       if os.path.isfile(input_path):
         if not generate_and_test(input_filename, source_dir, working_dir,
                                  fixup_path, pdfium_test_path):
-          os_exit_code = 1
+          failures.append(input_path)
 
-  return os_exit_code
+  if failures:
+    print '\n\nSummary of Failures:'
+    for failure in failures:
+      print failure
+    return 1
+  return 0
 
 
 if __name__ == '__main__':
   sys.exit(main())