In PatchIssue, add CL description to commit message

tests/git_cl_test.py

Index: tests/git_cl_test.py
diff --git a/tests/git_cl_test.py b/tests/git_cl_test.py
index f633581165cdbc6af2c56e06aab5eaec7e807686..cf5abf6c6e2524b6e6f17bc8561bd836b3f372de 100755
--- a/tests/git_cl_test.py
+++ b/tests/git_cl_test.py
@@ -871,6 +871,7 @@ class TestGitCl(TestCase):
   def _patch_common(self):
     self.mock(git_cl.Changelist, 'GetMostRecentPatchset', lambda x: '60001')
     self.mock(git_cl.Changelist, 'GetPatchSetDiff', lambda *args: None)
+    self.mock(git_cl.Changelist, 'GetDescription', lambda *args: 'Description')
     self.mock(git_cl.Changelist, 'SetIssue', lambda *args: None)
     self.mock(git_cl.Changelist, 'SetPatchset', lambda *args: None)
     self.mock(git_cl, 'IsGitVersionAtLeast', lambda *args: True)
@@ -887,6 +888,7 @@ class TestGitCl(TestCase):
     self.calls += [
       ((['git', 'apply', '--index', '-p0', '--3way'],), ''),
       ((['git', 'commit', '-m',
+         'Description\n\n' +
          'patch from issue 123456 at patchset 60001 ' +
          '(http://crrev.com/123456#ps60001)'],), ''),
     ]