Support KClass.functions and declaredFunctions

compiler/testData/codegen/boxWithStdlib/reflection/methodsFromAny/memberExtensionToString.kt

@@ -5,9 +5,16 @@ class A {
     var String.id: String
         get() = this
         set(value) {}
+
+    fun Int.foo(): Double = toDouble()
 }
 
 fun box(): String {
     val p = javaClass<A>().kotlin.extensionProperties.single()
     return if ("$p" == "var A.(kotlin.String.)id") "OK" else "Fail $p"
+
+    val q = javaClass<A>().kotlin.declaredFunctions.single()
+    if ("$q" != "fun A.(kotlin.Int.)foo(): kotlin.Double") return "Fail q $q"
+
+    return "OK"
 }