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

compiler/testData/klib/evolution/addEnumClassMember.kt

@@ -0,0 +1,32 @@
+// MODULE: lib
+// FILE: A.kt
+// VERSION: 1
+
+enum class X {
+    Y,
+    Z
+}
+
+// FILE: B.kt
+// VERSION: 2
+
+enum class X {
+    Y,
+    Z,
+    W
+}
+
+// MODULE: mainLib(lib)
+// FILE: mainLib.kt
+
+fun lib(): String = when {
+    X.values().map { it.name }.joinToString(", ") != "Y, Z, W" -> "fail 1"
+    X.valueOf("W").name != "W" -> "fail 2"
+
+    else -> "OK"
+}
+
+// MODULE: main(mainLib)
+// FILE: main.kt
+fun box(): String = lib()
+