Make parentheses necessary for '(x op return y) op z' #KT-16808 Fixed

idea/testData/intentions/removeUnnecessaryParentheses/elvisRhs.kt

@@ -0,0 +1,5 @@
+// IS_APPLICABLE: false
+// WITH_RUNTIME
+fun foo(): Boolean {
+    return <caret>("" ?: return false) in listOf("")
+}

idea/testData/intentions/removeUnnecessaryParentheses/elvisRhsEmptyReturn.kt

@@ -0,0 +1,7 @@
+// IS_APPLICABLE: false
+// WITH_RUNTIME
+fun foo() {
+    bar(<caret>("" ?: return) in listOf(""))
+}
+
+fun bar(arg: Boolean) {}