Do whitish flecks in front of radiator mean it's cracking and needs replacing?

What is your question?

My mechanic told me those light flecks in the pan in front of the radiator mean it's going to crack. The metal on top is dark, and in front it's lighter showing fine lines which mean it will soon leak and lose coolant. I believe it's an original radiator although I'm not positive. Thanks for any help you can give me!