[FIR-TEST] Add new testdata generated after changes in previous commit

compiler/testData/diagnostics/tests/when/DuplicatedLabels.fir.kt

@@ -0,0 +1,51 @@
+package test
+
+const val four = 4
+
+fun first(arg: Int) = when (arg) {
+    1 -> 2
+    2 -> 3
+    1 -> 4
+    4 -> 5
+    1 -> 6
+    2 -> 7
+    // Error should be here: see KT-11971
+    four -> 8
+    else -> 0
+}
+
+fun second(arg: String): Int {
+    when (arg) {
+        "ABC" -> return 0
+        "DEF" -> return 1
+        "ABC" -> return -1
+        "DEF" -> return -2
+    }
+    return 42
+}
+
+fun third(arg: Any?): Int {
+    when (arg) {
+        null -> return -1
+        is String -> return 0
+        is Double -> return 1
+        is Double -> return 2
+        null -> return 3
+        else -> return 5
+    }
+}
+
+enum class Color { RED, GREEN, BLUE }
+
+fun fourth(arg: Color) = when (arg) {
+    Color.RED -> "RED"
+    Color.GREEN -> "GREEN"
+    Color.RED -> "BLUE"
+    Color.BLUE -> "BLUE"
+}
+
+fun fifth(arg: Any?) = when (arg) {
+    is Any -> "Any"
+    else -> ""
+    else -> null
+}