Example failure: https://travis-ci.org/apache/incubator-mxnet/builds/450064964?utm_source=github_status&utm_medium=notification

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FAIL: test_gluon_rnn.test_layer_bidirectional

Traceback (most recent call last):
File "/usr/local/Cellar/numpy/1.14.5/libexec/nose/lib/python2.7/site-packages/nose/case.py", line 197, in runTest
self.test(*self.arg)
File "/Users/travis/build/apache/incubator-mxnet/tests/python/unittest/common.py", line 106, in test_new
orig_test(*args, **kwargs)
File "/Users/travis/build/apache/incubator-mxnet/tests/python/unittest/test_gluon_rnn.py", line 282, in test_layer_bidirectional
assert_allclose(net(data).asnumpy(), ref_net(data).asnumpy())
File "/usr/local/lib/python2.7/site-packages/numpy/testing/nose_tools/utils.py", line 1396, in assert_allclose
verbose=verbose, header=header, equal_nan=equal_nan)
File "/usr/local/lib/python2.7/site-packages/numpy/testing/nose_tools/utils.py", line 779, in assert_array_compare
raise AssertionError(msg)
AssertionError:
Not equal to tolerance rtol=1e-07, atol=0
(mismatch 0.0649350649351%)
x: array([[[0.682853, 0.674969, 0.547395, ..., 0.997481, 0.998059
0.994295]
[0.652577, 0.653787, 0.478821, ..., 0.997182, 0.996606,...
y: array([[[0.682853, 0.674969, 0.547395, ..., 0.997481, 0.998059
0.994295]
[0.652577, 0.653787, 0.478821, ..., 0.997182, 0.996606,...