Mountable creatures fail to block attacks for the riders

[RedShakespeare]

Describe the bug

Large-volume mountable animals don't block enemies' attacks as the comments in src/creature.cpp

Steps To Reproduce

Steps to reproduce the behavior:

1. Write a monster(whatever it is) with incredibly large _volume_attribute.(e.g.,100 times larger than human or more)
2. Make a player in game, summon this monster and ride on it.
3. Summon an enemy(zombie or something) and stay there let it hit the player&the mount.

Expected behavior

The larger the mounted monster is, the less chance the player is hit by enemy.

Screenshots

Cataclysm-DDA/src/creature.cpp

Lines 556 to 559 in cf4ce7d

	// If carrying a rider, there is a chance the hits may hit rider instead.
	// big mounts and small player = big shield for player.
	if( one_in( std::max( 2, get_size() - g->u.get_size() ) ) ) {
	g->u.deal_projectile_attack( source, attack, print_messages );

↑ the comment in src/creature.cpp

↑what actually happened when the player(87500 ml) was riding on a mod mon(87500000 ml)

Versions and configuration

• Game Version: [0.d-6692-gcf4ce7d or 0.d-9512]

Additional context

I must admit that this bug has misled one of my PRs(#33329 ) which failed to work in the same way.Guess this is because those codes in src/creature.cpp only cover those attacks aimed at the mounted monsters but fail to count in the ones directly aimed at the player itself.