It is not the proc that grant aggro, it is only the heal because you heal yourself.
In you combat log it is written something like :
Your Improved leader of the pack heals you for 800
Unfortunaltery I have no log with this here.
Earthshield and pom work the same way and give you heal aggro.
Here some logs :
5/1 01:01:44.906 Your Prayer of Mending heals you for 1745.
5/1 00:40:47.031 Your Earth Shield heals you for 729.
For lifebloom, only the last tick works this way, the hot part of lifebloom count for the druid :
5/1 00:12:21.515 Beldechan gains 247 health from Narutoto 's Lifebloom.
5/1 00:12:22.609 Beldechan gains 248 health from Narutoto 's Lifebloom.
5/1 00:12:23.218 Beldechan 's Lifebloom heals Beldechan for 1205.
For Defensive stance and defiance I never thought it could not be applied to heals (bandage, health potions ..) or other effects but it is a good question.
On the defiance description it is written "Increases the threat generated by all your ATTACKS by 5/10/15% while in defensive stance", so we can think it doesn't apply to heals, but if you check in thottbot spells details :
Defiance :
http://thottbot.com/s12789
Apply Aura: Mod Threat (All)
Value: 15
Defensive stance :
http://thottbot.com/s7376
Apply Aura: Mod Threat (All)
Value: 30
And for this aura "Mod threat (all)" you can found salvation, which indeed is working for heals, so I think def stance and defiance should apply to self heals.