Rationalizes the entire tracking of the linker object nodes, effecting
GLSL, HLSL, and SPIR-V, to allow tracked objects to be fully edited before
their type snapshot for linker objects.
Should only effect things when the rest of the AST contained no reference to
the symbol, because normal AST nodes were not stale. Also will only effect such
objects when their types were edited.
This fixes defects as follows:
1. handleLvalue could be called on a non-L-value, and it shouldn't be.
2. HLSL allows unary negation on non-bool values. TUnaryOperator::promote
can now promote other types (e.g, int, float) to bool for this op.
3. HLSL allows binary logical operations (&&, ||) on arbitrary types, similar
(2).
4. HLSL allows mod operation on arbitrary types, which will be promoted.
E.g, int % float -> float % float.
