Fix to failing test

It seems that even the last fix of the generated random numbers didn't do the trick. The reason being same numeric instability. I've change the operation to a sum, which, if you apply it recursevly is less problematic then multiplying numbers

Fix to failing test
27c5b8e1 · Razvan Pascanu · 976d2fb9 · 27c5b8e1
--- a/theano/scan_module/tests/test_scan.py
+++ b/theano/scan_module/tests/test_scan.py
@@ -2875,7 +2875,7 @@ class T_Scan(unittest.TestCase):
        # The test is based on the code provided by Timothy Lillicrap
        def onestep(xdl, xprev, w):
-            xnew = tensor.tanh(tensor.dot(w, xprev))
+            xnew = w + xprev
            return xnew
        xinit = tensor.tensor3('xinit')