"Hey Skeeter, I got you a shirt in every color for your birthday!" "Cool! Wow, you really got me a green one, an orange one ... but wait ... no white shirt?"
Yes, it's contrived, but you might say "No white shirt?" in any situation in which you expect a specific white shirt and it's not there.
You also might say this to an employee who's supposed to wear a white shirt as part of a uniform, but comes in with another color.
Usually yes, when you expect one or more but see none. But when you expect exactly one and see none, you would say "No white shirt". e.g., when someone was helping you find your white shirt (you only own one), they might come back later and say, "I looked all over the house. No white shirt. Sorry, you must have left it somewhere else."
The strong ending of Nomativ/Neuter nouns such as 'Hemd' is '-es' (from 'das').
'weiß' takes the strong '-es' ending because the preceding article 'kein' does not have the strong ending '-es'. If the preceding article does not have the strong ending, the adjective receives the strong ending by default.
For more on strong/weak endings, check out this video:
I agree -- it could be used in a situation such as "I'm going to wear a black shirt tonight." - "Not a white shirt?" (Ich ziehe mir heute Abend ein schwarzes Hemd an. -- Kein weißes Hemd?)
However, as far as I can tell, "Not a white shirt?" has been accepted for at least 2 years. (But the comment you replied to is 3 years old.)