Yes, although fasion is a fleeting thing from one year to the next, I believe that choice of clothing is some form of non-verbal communication. Whether or not being perceived as "flirty" was the desired effect of the woman is open to debate. Maybe she was going for "chic."

I think we are conditioned by advertising, industry, and our pop culture to initially think "flirt." We cannot know if she really is a flirt until we engage in conversation with her; but the thought is there . . . the impression is formed.