Use the right wording in DCHECK_IS_ON() presubmit check.

PRESUBMIT.py

 # Copyright (c) 2012 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.
 
 """Top-level presubmit script for Chromium.
 
 See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
 for more details about the presubmit API built into depot_tools.
 """
 
@@ skipping 413 matching lines @@
       if 'UNIT_TEST ' in line or line.endswith('UNIT_TEST'):
         problems.append('    %s:%d' % (f.LocalPath(), line_num))
 
   if not problems:
     return []
   return [output_api.PresubmitPromptWarning('UNIT_TEST is only for headers.\n' +
       '\n'.join(problems))]
 
 
 def _CheckDCHECK_IS_ONHasBraces(input_api, output_api):
-  """Checks to make sure DCHECK_IS_ON() does not skip the braces."""
+  """Checks to make sure DCHECK_IS_ON() does not skip the parentheses."""
   errors = []
   pattern = input_api.re.compile(r'DCHECK_IS_ON(?!\(\))',
                                  input_api.re.MULTILINE)
   for f in input_api.AffectedSourceFiles(input_api.FilterSourceFile):
     if (not f.LocalPath().endswith(('.cc', '.mm', '.h'))):
       continue
     for lnum, line in f.ChangedContents():
       if input_api.re.search(pattern, line):
         errors.append(output_api.PresubmitError(
           ('%s:%d: Use of DCHECK_IS_ON() must be written as "#if ' +
-           'DCHECK_IS_ON()", not forgetting the braces.')
+           'DCHECK_IS_ON()", not forgetting the parentheses.')
           % (f.LocalPath(), lnum)))
   return errors
 
 
 def _FindHistogramNameInLine(histogram_name, line):
   """Tries to find a histogram name or prefix in a line."""
   if not "affected-histogram" in line:
     return histogram_name in line
   # A histogram_suffixes tag type has an affected-histogram name as a prefix of
   # the histogram_name.
@@ skipping 1916 matching lines @@
       output_api,
       json_url='http://chromium-status.appspot.com/current?format=json'))
 
   results.extend(
       input_api.canned_checks.CheckPatchFormatted(input_api, output_api))
   results.extend(input_api.canned_checks.CheckChangeHasBugField(
       input_api, output_api))
   results.extend(input_api.canned_checks.CheckChangeHasDescription(
       input_api, output_api))
   return results