Use the right wording in DCHECK_IS_ON() presubmit check.

PRESUBMIT.py

Index: PRESUBMIT.py
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 6334c053cab7c5eb75be523cda003b623f61af7c..e56d4b37a95f927ef85965fe11363ceb3c3dedcc 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -431,7 +431,7 @@ def _CheckNoUNIT_TESTInSourceFiles(input_api, output_api):
 
 
 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)
@@ -442,7 +442,7 @@ def _CheckDCHECK_IS_ONHasBraces(input_api, output_api):
       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