[KLIB][tests] Keep "klib evolution" test data under "testData/klib/" dir

compiler/testData/klib/evolution/addingSealedClassMember.kt

@@ -0,0 +1,47 @@
+// MODULE: lib
+// FILE: A.kt
+// VERSION: 1
+
+sealed class X(val name: String ="X")
+
+class Y: X("Y")
+
+class Z: X("Z")
+
+fun last(): X = Z()
+
+// FILE: B.kt
+// VERSION: 2
+
+sealed class X(val name: String ="X")
+
+class Y: X("Y")
+
+class Z: X("Z")
+
+class W: X("W")
+          
+fun last(): X = W()
+
+// MODULE: mainLib(lib)
+// FILE: mainLib.kt
+
+fun lib(): String {
+    val x = last()
+    return when(x) {
+        is Y -> "fail 1"
+        is Z -> "fail 2"
+
+        else -> {
+            if (x.name == "W")
+                "OK"
+            else
+                "fail 3"
+        }
+    }
+}
+
+// MODULE: main(mainLib)
+// FILE: main.kt
+fun box(): String = lib()
+