FIR checker: warn useless as and is

compiler/testData/diagnostics/tests/sealed/ExhaustiveOnRoot.fir.kt

@@ -1,23 +0,0 @@
-sealed class Stmt
-
-class ForStmt : Stmt()
-
-sealed class Expr : Stmt() {
-    object BinExpr : Expr()
-}
-
-fun test(x: Stmt): String =
-        when (x) {
-            is Expr -> "expr"
-            is Stmt -> "stmt"
-        }
-
-fun test2(x: Stmt): String =
-        <!NO_ELSE_IN_WHEN!>when<!> (x) {
-            is Expr -> "expr"
-        }
-
-fun test3(x: Expr): String =
-        when (x) {
-            is Stmt -> "stmt"
-        }

compiler/testData/diagnostics/tests/sealed/ExhaustiveOnRoot.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 sealed class Stmt
 
 class ForStmt : Stmt()

compiler/testData/diagnostics/tests/sealed/NonExhaustiveWhenWithAnyCase.fir.kt

@@ -1,15 +0,0 @@
-sealed class Sealed {
-    object First: Sealed()
-    open class NonFirst: Sealed() {
-        object Second: NonFirst()
-        object Third: NonFirst()
-    }
-}
-
-fun foo(s: Sealed): Int {
-    return <!NO_ELSE_IN_WHEN!>when<!>(s) {
-        is Sealed.First -> 1
-        !is Any -> 0
-    }
-}
-

compiler/testData/diagnostics/tests/sealed/NonExhaustiveWhenWithAnyCase.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 sealed class Sealed {
     object First: Sealed()
     open class NonFirst: Sealed() {