Fix failing tests, copy testData

Some tests were using files that others called blackBoxFile() on. Since
those files are now moved to box/, copy them back to make the tests pass

compiler/testData/codegen/enum/abstractmethod.kt

@@ -0,0 +1,10 @@
+fun box() = IssueState.DEFAULT.ToString() + IssueState.FIXED.ToString()
+
+enum class IssueState {
+   DEFAULT
+   FIXED {
+       override fun ToString() = "K"
+   }
+
+   open fun ToString() : String = "O"
+}

compiler/testData/codegen/enum/name.kt

@@ -0,0 +1,6 @@
+enum class State {
+  O
+  K
+}
+
+fun box() = "${State.O.name()}${State.K.name()}"

compiler/testData/codegen/enum/simple.kt

@@ -0,0 +1,12 @@
+enum class Season {
+    WINTER
+    SPRING
+    SUMMER
+    AUTUMN
+}
+
+fun foo(): Season = Season.SPRING
+
+fun box() =
+    if (foo() == Season.SPRING) "OK"
+    else "fail"