Reapply r104938 "Make svn update not prompt during a sync."

tests/gclient_scm_test.py

Index: tests/gclient_scm_test.py
diff --git a/tests/gclient_scm_test.py b/tests/gclient_scm_test.py
index 6d5e380c0f9e2d18d9e64ff0255771611b2c3777..89e84d32fd5cfde0856027d0d75fc180dc7a4e90 100755
--- a/tests/gclient_scm_test.py
+++ b/tests/gclient_scm_test.py
@@ -73,6 +73,8 @@ class SVNWrapperTestCase(BaseTestCase):
       self.force = False
       self.reset = False
       self.nohooks = False
+      # TODO(maruel): Test --jobs > 1.
+      self.jobs = 1
 
   def Options(self, *args, **kwargs):
     return self.OptionsObject(*args, **kwargs)