private static boolean returnStatementsAreEquivalent(@NotNull GrReturnStatement statement1,
                                                       @NotNull GrReturnStatement statement2) {
    final GrExpression returnValue1 = statement1.getReturnValue();
    final GrExpression returnValue2 = statement2.getReturnValue();
    return expressionsAreEquivalent(returnValue1, returnValue2);
  }
private static boolean returnStatementsAreEquivalent(@NotNull GrReturnStatement statement1,
                                                       @NotNull GrReturnStatement statement2)