JS: make enum valueOf() throw if not found.

compiler/testData/codegen/box/enum/emptyEnumValuesValueOf.kt

@@ -1,6 +1,3 @@
-// TODO: muted automatically, investigate should it be ran for JS or not
-// IGNORE_BACKEND: JS
-
 enum class Empty
 
 fun box(): String {

compiler/testData/codegen/box/enum/valueof.kt

@@ -3,9 +3,20 @@ enum class Color {
   BLUE
 }
 
+fun throwsOnGreen(): Boolean {
+    try {
+        Color.valueOf("GREEN")
+        return false
+    }
+    catch (e: Exception) {
+        return true
+    }
+}
+
 fun box() = if(
      Color.valueOf("RED") == Color.RED
   && Color.valueOf("BLUE") == Color.BLUE
   && Color.values()[0] == Color.RED
   && Color.values()[1] == Color.BLUE
-  ) "OK" else "fail"
+  && throwsOnGreen()
+  ) "OK" else "fail"