Don't throw an error if no http tests are run! TBR.

webkit/tools/layout_tests/run_webkit_tests.py

 #!/bin/env python
 # Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Run layout tests using the test_shell.
 
 This is a port of the existing webkit test script run-webkit-tests.
 
 The TestRunner class runs a series of tests (TestType interface) against a set
@@ skipping 331 matching lines @@
         tests_by_dir[directory] = []
       tests_by_dir[directory].append((test_file,
           path_utils.FilenameToUri(test_file)))
 
     # Sort by the number of tests in the dir so that the ones with the most
     # tests get run first in order to maximize parallelization. Number of tests
     # is a good enough, but not perfect, approximation of how long that set of
     # tests will take to run. We can't just use a PriorityQueue until we move
     # to Python 2.6.
     test_lists = []
+    http_tests = None
     for directory in tests_by_dir:
       test_list = tests_by_dir[directory]
       # Keep the tests in alphabetical order.
       # TODO: Remove once tests are fixed so they can be run in any order.
       test_list.reverse()
       test_list_tuple = (directory, test_list)
       if directory == 'LayoutTests' + os.sep + 'http':
         http_tests = test_list_tuple
       else:
         test_lists.append(test_list_tuple)
     test_lists.sort(lambda a, b: cmp(len(b), len(a)))
 
     # Put the http tests first. There are only a couple hundred of them, but
     # each http test takes a very long time to run, so sorting by the number
     # of tests doesn't accurately capture how long they take to run.
-    test_lists.insert(0, http_tests)
+    if http_tests:
+      test_lists.insert(0, http_tests)
 
     filename_queue = Queue.Queue()
     for item in test_lists:
       filename_queue.put(item)
     return filename_queue
 
   def _GetTestShellArgs(self, index):
     """Returns the tuple of arguments for tests and for test_shell."""
     shell_args = []
     test_args = test_type_base.TestArguments()
@@ skipping 582 matching lines @@
   option_parser.add_option("", "--run-part",
                            default=None,
                            help=("Run a specified part (n:m), the nth of m"
                                  " parts, of the layout tests"))
   option_parser.add_option("", "--batch-size",
                            default=None,
                            help=("Run a the tests in batches (n), after every "
                                  "n tests, the test shell is relaunched."))
   options, args = option_parser.parse_args()
   main(options, args)