Fix the mocks.py for 2.0 unittests

The recent change to use LogWarning with multiple arguments in
mpcu.py/HooksMaster broke the (simple) mock we have in the tests.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Michael Hanselmann <hansmi@google.com>

test/mocks.py

@@ -55,12 +55,16 @@ class FakeConfig:
 class FakeProc:
     """Fake processor object"""
 
-    def LogWarning(self, msg):
+    def LogWarning(self, msg, *args, **kwargs):
         pass
 
-    def LogInfo(self, msg):
+    def LogInfo(self, msg, *args, **kwargs):
         pass
 
+    def LogStep(self, current, total, message):
+        pass
+
+
 class FakeContext:
     """Fake context object"""