As I didn't want a bunch of rotten flesh in my inventory, I went to the survival inventory of creative GUI menu, and put my cursor over the rotten flesh and pressed,"Ctr-Q"
(control-Q)
The whole stack (64) flew out as normal. I left my inventory and went to the empty spot in my hot bar. I accidentally right-clicked and the stack popped back in my hand. The items I dropped were still lying on the ground though.

This does not happen is survival mode.