git cl for Gerrit: make --squash generate Change-Id directly.

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 65b5be7ec373b9528b1a3ae2bf0dbdd9d8e945d5..8bf4679c4fe3f46b2ce0f296cf1108f8c6214cb8 100755
--- a/tests/git_cl_test.py
+++ b/tests/git_cl_test.py
@@ -17,6 +17,7 @@ from testing_support.auto_stub import TestCase
 
 import git_cl
 import git_common
+import git_footers
 import subprocess2
 
 class PresubmitMock(object):
@@ -588,7 +589,7 @@ class TestGitCl(TestCase):
            'fake_ancestor_sha..HEAD'],),
          description)
         ]
-    if git_cl.CHANGE_ID not in description:
+    if not git_footers.get_footer_change_id(description) and not squash:
       calls += [
           ((['git', 'log', '--pretty=format:%s\n\n%b',
              'fake_ancestor_sha..HEAD'],),