Rename one typeinf_ext method to typeinf_ext_toplevel

This disambiguates the two methods, allowing us to eliminate the
redundant `world::UInt` parameter.

base/compiler/compiler.jl

@@ -109,7 +109,7 @@ include("compiler/typeinfer.jl")
 include("compiler/optimize.jl") # TODO: break this up further + extract utilities
 
 include("compiler/bootstrap.jl")
-ccall(:jl_set_typeinf_func, Cvoid, (Any,), typeinf_ext)
+ccall(:jl_set_typeinf_func, Cvoid, (Any,), typeinf_ext_toplevel)
 
 end # baremodule Compiler
 ))

base/compiler/typeinfer.jl

@@ -600,9 +600,9 @@ function typeinf_type(interp::AbstractInterpreter, method::Method, @nospecialize
     return widenconst(frame.result)
 end
 
-# This is a bridge for the C code calling `jl_typinf_func()`
-typeinf_ext(mi::MethodInstance, world::UInt) = typeinf_ext(NativeInterpreter(world), mi, world)
-function typeinf_ext(interp::AbstractInterpreter, linfo::MethodInstance, world::UInt)
+# This is a bridge for the C code calling `jl_typeinf_func()`
+typeinf_ext_toplevel(mi::MethodInstance, world::UInt) = typeinf_ext_toplevel(NativeInterpreter(world), mi)
+function typeinf_ext_toplevel(interp::AbstractInterpreter, linfo::MethodInstance)
     if isa(linfo.def, Method)
         # method lambda - infer this specialization via the method cache
         src = typeinf_ext(interp, linfo)