restructured control flow tests

compiler/testData/cfg/declarations/multiDeclaration/MultiDecl.kt

@@ -0,0 +1,11 @@
+package n
+
+class C {
+    fun component1() = 1
+    fun component2() = 2
+}
+
+fun test(c: C) {
+    val (a, b) = c
+    val d = 1
+}