Fix ShaderStorageBufferTest31.LoadAndStoreBooleanVarAndArray to be more correct
Fix ShaderStorageBufferTest31.LoadAndStoreBooleanVarAndArray to be more correct

The test contained bugs which made it fail on multiple platforms.
After mapping SSBO, access the data with GLuint instead of GLboolean.
The elements in the SSBO are 4 machine units, even though the SSB
talks about bools.

A bvec2 declared after bool in the SSB has alignment requirements.

The test asserts that a shader written result is zero. In this case
it needs to initialize the result buffer to non-zero in order to
prove that the shader put the zero there.

Bug: angleproject:3749, angleproject:1951
Change-Id: Iad8301be7f9e9df6bbed6b390d9c415d4e437c1a
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1738909
Commit-Queue: Kimmo Kinnunen FI <07aa763417bee97d7b7eaa023ff0eef37ee250ec@nvidia.com>
Reviewed-by: Yuly Novikov <36f5580f63d0a3eacc17e89a61d11e2f646630d2@chromium.org>

ppy/angle,ppy/angle,ppy/angle,ppy/angle