Fix non-square matrix uniform packing. This was broken in two places: the register count was using the non- transposed matrix row count. The block layout encoder was also not set to transpose matrices, which was causing incorrect packing info to be calculated in link. BUG=angleproject:1923 Change-Id: I89094aa116fad4bda15f018498f8637520f12bd4 Reviewed-on: https://chromium-review.googlesource.com/454876 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org> Reviewed-by: Olli Etuaho <oetuaho@nvidia.com>