Update from chromium https://crrev.com/302282

base/PRESUBMIT.py

Index: base/PRESUBMIT.py
diff --git a/base/PRESUBMIT.py b/base/PRESUBMIT.py
index 4e9e64bcf2c18009b509e43ed3842b4aee32b58b..4b366d9322a45005a38c09202d301da77ed5d051 100644
--- a/base/PRESUBMIT.py
+++ b/base/PRESUBMIT.py
@@ -46,17 +46,3 @@ def CheckChangeOnCommit(input_api, output_api):
   results = []
   results.extend(_CommonChecks(input_api, output_api))
   return results
-
-
-def GetPreferredTryMasters(project, change):
-  return {
-    'tryserver.chromium.linux': {
-      'linux_chromium_rel': set(['defaulttests']),
-    },
-    'tryserver.chromium.mac': {
-      'mac_chromium_rel': set(['defaulttests']),
-    },
-    'tryserver.chromium.win': {
-      'win_chromium_rel': set(['defaulttests']),
-    }
-  }