When to if now add braces for if branches inside #KT-12942 Fixed

(cherry picked from commit 29a7bfe)

idea/testData/intentions/branched/ifWhen/whenToIf/whenWithIf.kt

@@ -0,0 +1,11 @@
+// KT-12942: when to if changes semantics
+fun test(b: Boolean): String {
+    <caret>when (b) {
+        true ->
+            if (true) return "first"
+        false ->
+            if (true) return "second"
+    }
+
+    return "none"
+}

idea/testData/intentions/branched/ifWhen/whenToIf/whenWithIf.kt.after

@@ -0,0 +1,10 @@
+// KT-12942: when to if changes semantics
+fun test(b: Boolean): String {
+    if (b == true) {
+        if (true) return "first"
+    } else if (b == false) {
+        if (true) return "second"
+    }
+
+    return "none"
+}