test cleanup: Remove skipIf test decorator

We use this from time to time to skip tests for various reasons. It's
not currently in use. But if it's needed, we should use
testtools.testcase.skipIf, which does the same thing, rather than
carrying our own copy around.

Change-Id: I422fe0bc4d761a374daaf0bf1043d5b8fb41d449

nova/test.py

@@ -121,38 +121,6 @@ class TestingException(Exception):
     pass
 
 
-class skipIf(object):
-    def __init__(self, condition, reason):
-        self.condition = condition
-        self.reason = reason
-
-    def __call__(self, func_or_cls):
-        condition = self.condition
-        reason = self.reason
-        if inspect.isfunction(func_or_cls):
-            @six.wraps(func_or_cls)
-            def wrapped(*args, **kwargs):
-                if condition:
-                    raise testtools.TestCase.skipException(reason)
-                return func_or_cls(*args, **kwargs)
-
-            return wrapped
-        elif inspect.isclass(func_or_cls):
-            orig_func = getattr(func_or_cls, 'setUp')
-
-            @six.wraps(orig_func)
-            def new_func(self, *args, **kwargs):
-                if condition:
-                    raise testtools.TestCase.skipException(reason)
-                orig_func(self, *args, **kwargs)
-
-            func_or_cls.setUp = new_func
-            return func_or_cls
-        else:
-            raise TypeError('skipUnless can be used only with functions or '
-                            'classes')
-
-
 # NOTE(claudiub): this needs to be called before any mock.patch calls are
 # being done, and especially before any other test classes load. This fixes
 # the mock.patch autospec issue: