Add presubmit check for Google support URL format.

PRESUBMIT.py

Index: PRESUBMIT.py
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 2284a0f5d46ae3d8251ab9250989466623bf0c6e..e11c562bf69b935c6c92dc8fae59a4fe0039bddc 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -975,6 +975,21 @@ def _CheckForVersionControlConflicts(input_api, output_api):
       'Version control conflict markers found, please resolve.', errors))
   return results
 
+def _CheckGoogleSupportAnswerUrl(input_api, output_api):
+  pattern = input_api.re.compile('support\.google\.com\/chrome.*/answer')
+  errors = []
+  for f in input_api.AffectedFiles():
+    for line_num, line in f.ChangedContents():
+      if pattern.search(line):
+        errors.append('    %s:%d %s' % (f.LocalPath(), line_num, line))
+
+  results = []
+  if errors:
+    results.append(output_api.PresubmitPromptWarning(
+      'Found Google support URL addressed by answer number. Please replace with '
+      'a p= identifier instead. See crbug.com/679462\n', errors))
+  return results
+
 
 def _CheckHardcodedGoogleHostsInLowerLayers(input_api, output_api):
   def FilterFile(affected_file):
@@ -2296,6 +2311,7 @@ def CheckChangeOnUpload(input_api, output_api):
   results.extend(_CheckUmaHistogramChanges(input_api, output_api))
   results.extend(_AndroidSpecificOnUploadChecks(input_api, output_api))
   results.extend(_CheckSyslogUseWarning(input_api, output_api))
+  results.extend(_CheckGoogleSupportAnswerUrl(input_api, output_api))
   return results