code: public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
                                          Type site, Name name,
                                          List<Type> argtypes,
                                          List<Type> typeargtypes) {
          MethodResolutionContext resolveContext = new MethodResolutionContext();
          resolveContext.internalResolution = true;
          Symbol sym = resolveQualifiedMethod(resolveContext, pos, env, site.tsym,
                  site, name, argtypes, typeargtypes);
          if (sym.kind == MTH) return (MethodSymbol)sym;
          else throw new FatalError(
                   diags.fragment("fatal.err.cant.locate.meth",
                                  name));
      }
docs: Resolve a qualified method identifier, throw a fatal error if not
  found.
  @param pos       The position to use for error reporting.
  @param env       The environment current at the method invocation.
  @param site      The type of the qualifying expression, in which
  identifier is searched.
  @param name      The identifier's name.
  @param argtypes  The types of the invocation's value arguments.
  @param typeargtypes  The types of the invocation's type arguments.