Ice ball throwing subtitle is inconsistent with other throwable items

Relates to MC-312367 and MC-312362.

When throwing a newly-implemented ice ball, the caption shown is “Ice Ball flies”. This is inconsistent with the corrected subtitles which were fixed in the preceding snapshot, which say “[item] is thrown”.

To reproduce, throw an ice ball, a splash potion, and a bottle o' enchanting with captions enabled.

Expected results: all three show “is thrown”

Actual results: only two show “is thrown”; Ice Ball incorrectly shows “flies”