Remove LOG line checking from presubmit

PRESUBMIT.py

Index: PRESUBMIT.py
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index f8516afc44ef50ac5390f94aaa4acd7a5e86d31c..60a5fd773078053593b4fd1d124b1d04370a8625 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -242,32 +242,15 @@ def _SkipTreeCheck(input_api, output_api):
   return input_api.environ.get('PRESUBMIT_TREE_CHECK') == 'skip'
 
 
-def _CheckChangeLogFlag(input_api, output_api, warn):
-  """Checks usage of LOG= flag in the commit message."""
-  results = []
-  if (input_api.change.BUG and input_api.change.BUG != 'none' and
-      not 'LOG' in input_api.change.tags):
-    text = ('An issue reference (BUG=) requires a change log flag (LOG=). '
-            'Use LOG=Y for including this commit message in the change log. '
-            'Use LOG=N or leave blank otherwise.')
-    if warn:
-      results.append(output_api.PresubmitPromptWarning(text))
-    else:
-      results.append(output_api.PresubmitError(text))
-  return results
-
-
 def CheckChangeOnUpload(input_api, output_api):
   results = []
   results.extend(_CommonChecks(input_api, output_api))
-  results.extend(_CheckChangeLogFlag(input_api, output_api, True))
   return results
 
 
 def CheckChangeOnCommit(input_api, output_api):
   results = []
   results.extend(_CommonChecks(input_api, output_api))
-  results.extend(_CheckChangeLogFlag(input_api, output_api, False))
   results.extend(input_api.canned_checks.CheckChangeHasDescription(
       input_api, output_api))
   if not _SkipTreeCheck(input_api, output_api):