[Release] Remove usage of roll ref

tools/release/test_mergeinfo.py

Index: tools/release/test_mergeinfo.py
diff --git a/tools/release/test_mergeinfo.py b/tools/release/test_mergeinfo.py
index 4959b6de0dc2365f82cb6022f9446c2ce65a2aab..d455fa23748011a7d284e9f7c49b7a12c9729e3e 100755
--- a/tools/release/test_mergeinfo.py
+++ b/tools/release/test_mergeinfo.py
@@ -151,18 +151,6 @@ class TestMergeInfo(unittest.TestCase):
     self.assertTrue(hash_of_hit in merges)
     self.assertTrue(hash_of_ignored not in merges)
 
-  def testIsRolling(self):
-    commits = self._get_commits()
-    hash_of_first_commit = commits[0]
-    self._make_empty_commit('This one is the roll head')
-    self._execute_git(['branch', 'remotes/origin/roll'])
-    hash_of_not_rolled = self._make_empty_commit('This one is not yet rolled')
-
-    self.assertTrue(mergeinfo.is_rolling(
-      self.base_dir, hash_of_first_commit))
-    self.assertFalse(mergeinfo.is_rolling(
-      self.base_dir, hash_of_not_rolled))
-
   def testIsLkgr(self):
     commits = self._get_commits()
     hash_of_first_commit = commits[0]