The new parameters are: swizzleR, swizzleG, swizzleB, swizzleA.

Also, parameters sent from the context that can be either
originating from the Texture object or the Sampler object
are now sent from the correct origin.

An implementation for the swizzleR, swizzleG, swizzleB, swizzleA
parameters was done in SamplerCore. All related dEQP tests pass.

Change-Id: I45405a0d241d0e70a91a3c56357c7bc04c7dc75a
Reviewed-on: https://swiftshader-review.googlesource.com/4017Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>