[Piglit] [PATCH 0/2] Add tests for arb_texture_storage_multisample

[Chris Forbes]

These patches add tests for the TEXTURE_IMMUTABLE_FORMAT handling in ARB_texture_storage_multisample, and the various error behavior with [Get]TexParameter*().

Textures specified via TexStorage*Multisample are otherwise identical to those
via TexImage*Multisample, so tests for the rest of the multisample texture functionality are not duplicated here.