Basic class members generation.

Split testData into 'classes' and 'expressions'.

compiler/testData/ir/irText/classes/classMembers.kt

@@ -0,0 +1,39 @@
+class C(x: Int, val y: Int, var z: Int = 1) {
+    constructor() : this(0, 0, 0) {}
+
+    val property: Int = 0
+
+    val propertyWithGet: Int
+        get() = 42
+
+    var propertyWithGetAndSet: Int
+        get() = z
+        set(value) {
+            z = value
+        }
+
+    fun function() {
+        println("1")
+    }
+
+    fun Int.memberExtensionFunction() {
+        println("2")
+    }
+
+    class NestedClass {
+        fun function() {
+            println("3")
+        }
+
+        fun Int.memberExtensionFunction() {
+            println("4")
+        }
+    }
+
+    interface NestedInterface {
+        fun foo()
+        fun bar() = foo()
+    }
+
+    companion object
+}