fix the unittest problem caused by setitem doesn't support fp16

Author: zyfncg

python/paddle/fluid/tests/unittests/test_tensor_fill_.py

@@ -40,12 +40,11 @@ def test_tensor_fill_true(self):
             for dtype in typelist:
                 var = 1.
                 tensor = paddle.to_tensor(np_arr, place=p, dtype=dtype)
-                newtensor = tensor.clone()
-                newtensor[...] = var
+                target = tensor.numpy()
+                target[...] = var
 
                 tensor.fill_(var)  #var type is basic type in typelist
-                self.assertEqual((tensor.numpy() == newtensor.numpy()).all(),
-                                 True)
+                self.assertEqual((tensor.numpy() == target).all(), True)
 
     def test_tensor_fill_backward(self):
         typelist = ['float32']

python/paddle/fluid/tests/unittests/test_tensor_zero_.py

@@ -35,12 +35,11 @@ def test_tensor_fill_true(self):
                 np.array(six.moves.range(np.prod(self.shape))), self.shape)
             for dtype in typelist:
                 tensor = paddle.to_tensor(np_arr, place=p, dtype=dtype)
-                newtensor = tensor.clone()
-                newtensor[...] = 0
+                target = tensor.numpy()
+                target[...] = 0
 
                 tensor.zero_()
-                self.assertEqual(
-                    (tensor.numpy() == newtensor.numpy()).all().item(), True)
+                self.assertEqual((tensor.numpy() == target).all().item(), True)
 
 
 if __name__ == '__main__':