[Mesa-dev] Basic GLSL 1.50 support: new types & built-in functions

[Kenneth Graunke]

This series improves our basic GLSL 1.50 support.  First, it makes 1.50
shaders using built-in functions work.  Secondly, it adds the new types
and built-ins from the ARB_texture_multisample extension (which are now
part of core).

It also makes it possible to run Unigine Valley and Heaven 4.0 with
MESA_GL_VERSION_OVERRIDE=3.2 and MESA_GLSL_VERSION_OVERRIDE=150; i965
also needs shader_precompile=false to avoid an assertion failure which
I haven't tracked down yet.