[FIR] Update testdata of FIR spec tests

compiler/tests-spec/testData/diagnostics/notLinked/coercion-to-unit/neg/1.fir.kt

@@ -1,11 +1,20 @@
+/*
+ * KOTLIN DIAGNOSTICS NOT LINKED SPEC TEST (NEGATIVE)
+ *
+ * SECTIONS: coercion-to-unit
+ * NUMBER: 1
+ * DESCRIPTION: Coercion to Unit error diagnostics absence
+ * ISSUES: KT-38490
+ */
+
 // TESTCASE NUMBER: 1
 
 val y0 = when (2) {
-    else -> if (true) {""}
+    else -> <!INVALID_IF_AS_EXPRESSION!>if<!> (true) {""}
 }
 
 val w:Any = TODO()
 
 val y1 = when (2) {
-    else -> if (true) {""} // false ok with coercion to Unit
+    else -> <!INVALID_IF_AS_EXPRESSION!>if<!> (true) {""} // false ok with coercion to Unit
 }

compiler/tests-spec/testData/diagnostics/notLinked/dfa/pos/62.fir.kt

@@ -2,6 +2,15 @@
 // !DIAGNOSTICS: -UNUSED_EXPRESSION -ASSIGNED_BUT_NEVER_ACCESSED_VARIABLE -UNUSED_PARAMETER -UNUSED_VARIABLE -UNUSED_VALUE -VARIABLE_WITH_REDUNDANT_INITIALIZER
 // SKIP_TXT
 
+/*
+ * KOTLIN DIAGNOSTICS NOT LINKED SPEC TEST (POSITIVE)
+ *
+ * SECTIONS: dfa
+ * NUMBER: 62
+ * DESCRIPTION: Raw data flow analysis test
+ * HELPERS: classes, objects, typealiases, functions, enumClasses, interfaces, sealedClasses
+ */
+
 /*
  * TESTCASE NUMBER: 1
  * UNEXPECTED BEHAVIOUR
@@ -145,7 +154,7 @@ fun case_10(x: Any): String {
  */
 fun case_11(x: Any?): String? {
     if (x is Nothing?) {
-        return when(x) {
+        return <!NO_ELSE_IN_WHEN!>when<!>(x) {
             null -> null
         }
     }
@@ -159,7 +168,7 @@ fun case_11(x: Any?): String? {
  */
 fun case_12(x: Any?): String? {
     if (x == null) {
-        return when(x) {
+        return <!NO_ELSE_IN_WHEN!>when<!>(x) {
             null -> null
         }
     }
@@ -173,7 +182,7 @@ fun case_12(x: Any?): String? {
  */
 fun case_13(x: Any?): String? {
     if (x === null) {
-        return when(x) {
+        return <!NO_ELSE_IN_WHEN!>when<!>(x) {
             null -> null
         }
     }
@@ -187,7 +196,7 @@ fun case_13(x: Any?): String? {
  */
 fun case_14(x: Any?): String? {
     x as Nothing?
-    return when(x) {
+    return <!NO_ELSE_IN_WHEN!>when<!>(x) {
         null -> null
     }
 }