Extract Function: Support implicit abnormal exits via Nothing-typed expressions

idea/testData/refactoring/extractFunction/controlFlow/throws/implicitThrow.kt.after

@@ -0,0 +1,11 @@
+// WITH_RUNTIME
+// PARAM_DESCRIPTOR: value-parameter a: kotlin.Int? defined in foo
+// PARAM_TYPES: kotlin.Int?
+fun foo(a: Int?): Int {
+    return i(a)
+}
+
+private fun i(a: Int?): Int {
+    val n = a ?: error("")
+    return n + 1
+}