public CFGBuilder pushExpression(@NotNull PsiExpression expression, @Nullable NullabilityProblemKind<? super PsiExpression> kind) {
    if (kind == null) {
      return pushExpression(expression);
    }
    myAnalyzer.addCustomNullabilityProblem(expression, kind);
    expression.accept(myAnalyzer);
    myAnalyzer.removeCustomNullabilityProblem(expression);
    return this;
  }
public CFGBuilder pushExpression(@NotNull PsiExpression expression, @Nullable NullabilityProblemKind<? super PsiExpression> kind)