Support mapping between Kotlin functions and JVM methods/constructors

compiler/testData/codegen/boxAgainstJava/reflection/mapping/javaMethods.kt

@@ -0,0 +1,19 @@
+import kotlin.reflect.*
+import kotlin.reflect.jvm.*
+import javaMethods as J
+
+fun box(): String {
+    val f = J::f
+    val fm = f.javaMethod ?: return "Fail: no Method for f"
+    if (fm.invoke(J(), "abc") != "abc") return "Fail fm"
+    val ff = fm.kotlinFunction ?: return "Fail: no KFunction for fm"
+    if (f != ff) return "Fail f != ff"
+
+    val g = J::g
+    val gm = g.javaMethod ?: return "Fail: no Method for g"
+    if (gm.invoke(null, "ghi") != "ghi") return "Fail gm"
+    val gg = gm.kotlinFunction ?: return "Fail: no KFunction for gm"
+    if (g != gg) return "Fail g != gg"
+
+    return "OK"
+}