Getting method's function type from the MethodMirror instance in Scala

Assume I have an instance of MethodMirror created for a certain method of an object. By mirror's fields I can easily access return type and parameters of the method. But I actually need to obtain the type this method would have as a function.

Here is a toy code example which will help me explain, what I want to achieve. I'm using Scala 2.11.6.

import scala.reflect.runtime.universe._

object ForStackOverflow {
  object Obj {
    def method(x:String, y:String):Int = 0
    def expectedRetType():((String, String) => Int) = ???
  }

  def main(args: Array[String]) {
    val mirror:Mirror = runtimeMirror(getClass.getClassLoader)
    val instanceMirror = mirror.reflect(Obj)

    val methodSymbol:MethodSymbol = instanceMirror.symbol.toType.decl(TermName("method")).asMethod
    val methodMirror = instanceMirror.reflectMethod(methodSymbol)

    println(methodMirror.symbol.returnType)
    println(methodMirror.symbol.paramLists(0).map { x => x.info.resultType }.mkString(", "))

    val expectedSymbol:MethodSymbol = instanceMirror.symbol.toType.decl(TermName("expectedRetType")).asMethod
    println("I would like to produce from a 'methodMirror' this: "+expectedSymbol.returnType)
  }
}

I want to produce Type instance from the methodMirror which would represent a function. For this example it should be (String, String) => Int. I would prefer a solution that doesn't depend too much on the concrete Scala's FunctionX classes.