Broken again on nightly

[timholy]

julia> @descend weighted_color_mean(0.5, RGB(0.9, 0.6, 0.1), RGB(0.9, 0.7, 0.2))
ERROR: MethodError: no method matching optimize(::Core.Compiler.OptimizationState, ::Core.Compiler.OptimizationParams, ::Type{Any})
Stacktrace:
 [1] do_typeinf_slottypes
   @ ~/.julia/packages/Cthulhu/31ncW/src/reflection.jl:253 [inlined]
 [2] _descend(mi::Core.MethodInstance; iswarn::Bool, params::Core.Compiler.NativeInterpreter, optimize::Bool, interruptexc::Bool, kwargs::Base.Iterators.Pairs{Union{}, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})
   @ Cthulhu ~/.julia/packages/Cthulhu/31ncW/src/Cthulhu.jl:161