This fixes all these tests:
dEQP-GLES2.functional.shaders.functions.datatypes.float_mat*
dEQP-GLES2.functional.shaders.functions.datatypes.mat*
dEQP-GLES2.functional.shaders.linkage.varying_type_mat*
dEQP-GLES2.functional.shaders.matrix.*
dEQP-GLES2.functional.uniform_api.value.assigned.by_pointer.render.basic.mat2_*
dEQP-GLES2.functional.uniform_api.value.assigned.by_pointer.render.basic.mat3_*
dEQP-GLES2.functional.shaders.conversions.matrix_to_matrix.*
dEQP-GLES2.functional.shaders.conversions.matrix_combine.*
dEQP-GLES2.functional.shaders.random.scalar_conversion*

Bug:angleproject:2581
Bug:angleproject:2583
Bug:angleproject:2584
Bug:angleproject:2588
Change-Id: Ib8c03397f0229432292c51f4a6332f954fc8fa12
Reviewed-on: https://chromium-review.googlesource.com/1080392
Commit-Queue: Luc Ferron <lucferron@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>