Fix presubmit_scheme_histograms.py and presubmit_bad_message_reasons.py

content/browser/PRESUBMIT.py

 # Copyright 2017 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.
 
 """Chromium presubmit script to check that BadMessage enums in histograms.xml
 match the corresponding bad_message.h file.
 """
 
+def CheckChangeOnCommit(input_api, output_api):
+  return _CommonChecks(input_api, output_api)
+
+def CheckChangeOnUpload(input_api, output_api):
+  return _CommonChecks(input_api, output_api)
+
 def _RunHistogramChecks(input_api, output_api, histogram_name):
   try:
-    # Setup sys.path so that we can call histrogram code
+    # Setup sys.path so that we can call histograms code.
     import sys
     original_sys_path = sys.path
     sys.path = sys.path + [input_api.os_path.join(
       input_api.change.RepositoryRoot(),
       'tools', 'metrics', 'histograms')]
 
     import presubmit_bad_message_reasons
     return presubmit_bad_message_reasons.PrecheckBadMessage(input_api,
       output_api, histogram_name)
   except Exception as e:
     return [output_api.PresubmitError("Error verifying histogram (%s)."
       % str(e))]
   finally:
     sys.path = original_sys_path
 
-def CheckChangeOnUpload(input_api, output_api):
+def _CommonChecks(input_api, output_api):
   return _RunHistogramChecks(input_api, output_api, "BadMessageReasonContent")