regardless of the implementation or categories.

- use correct function names for rpcrt functions
- use CryptGenRandom to create unique serial numbers

The current GLSL cmp instruction is incorrect, because:
- it ignores destination write mask
- it ignores source swizzle
- it ignores other source modifiers.
- it works incorrectly for src0 = 0

Add some more tests for ITypeInfo::Invoke.

A callback function for computing the variance puts the computed value 
into the same field as a conformance, so make sure to copy the value 
into pCount before returning from ComputeConformanceOrVariance.

their names make more sense.