Fix first reshape in pixel_shuffle conversion (#21486)
Summary:
When converting pixel_shuffle to reshape + transpose + reshape, the first reshape should
be:
[N, C * r^2, H, W] => [N, C, r, r, H, W]
in order to match pytorch's implementation (see ATen PixelShuffle.cpp).
This previously wasn't caught by the test case, since it uses C = r = 4. Updated test case to
have C = 2, r = 4.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/21486
Reviewed By: houseroad
Differential Revision: D15700945
Pulled By: houseroad
fbshipit-source-id: 47019691fdc20e152e867c7f6fd57da104a12948
