[Eager]Fix VarWrapper isintance type problem (#1085)

* [Eager]Support dygraph2program for Eager Mode without program_desc_tracing

* [Eager]Fix VarWrapper isintance type problem
Co-authored-by: Nwhs <wanghaoshuang@baidu.com>

paddleslim/core/graph_wrapper.py

@@ -37,7 +37,7 @@ OPTIMIZER_OPS = [
 
 class VarWrapper(object):
     def __init__(self, var, graph):
-        assert isinstance(var, Variable)
+        assert isinstance(var, (Variable, Parameter))
         assert isinstance(graph, GraphWrapper)
         self._var = var
         self._graph = graph