Player heads with invalid texture data display the missing texture rather than a default skin

If a player head with invalid player data is given, it usually defaults to one of the nine standard skins. There are, however, ways to make it display the missing texture instead, which is not supposed to happen (it exists to indicate resource issues).

Example commands:

/give @p player_head[profile={texture:"error"}]

/give @p player_head[profile="#"]

Expected results: both would give heads with one of the default skin textures

Actual results: the bottom correctly gives a Steve head, but the top gives a magenta cube.

How to fix: if a valid texture cannot be loaded for a head, pick one of the defaults (like is done in most cases).