This has come up in the past and I don't believe it was resolved any of the other times either, but here is the argument I have put forth:
The Outsider template gives you features and traits.
Features: An outsider has the following features.
—8-sided Hit Dice.
—Base attack bonus equal to total Hit Dice (as fighter).
—Good Fortitude, Reflex, and Will saves.
—Skill points equal to (8 + Int modifier, minimum 1) per Hit Die, with quadruple skill points for the first Hit Die.
Traits: An outsider possesses the following traits (unless otherwise noted in a creature’s entry).
—Darkvision out to 60 feet.
—Unlike most other living creatures, an outsider does not have a dual nature—its soul and body form one unit. When an outsider is slain, no soul is set loose. Spells that restore souls to their bodies, such as raise dead, reincarnate, and resurrection, don’t work on an outsider. It takes a different magical effect, such as limited wish, wish, miracle, or true resurrection to restore it to life. An outsider with the native subtype can be raised, reincarnated, or resurrected just as other living creatures can be.
—Proficient with all simple and martial weapons and any weapons mentioned in its entry.
—Proficient with whatever type of armor (light, medium, or heavy) it is described as wearing, as well as all lighter types. Outsiders not indicated as wearing armor are not proficient with armor. Outsiders are proficient with shields if they are proficient with any form of armor.
—Outsiders breathe, but do not need to eat or sleep (although they can do so if they wish). Native outsiders breathe, eat, and sleep.
In the PHB, races have traits and classes have features. Racial traits do not depend on hit dice, class features do. If you follow that naming convention, then the outsider without racial hit dice gets all the traits and none of the feature listed under the outsider template.
It is worth noting, I would not say that aasimar would gain any armor proficiencies as the only entry given is for an aasimar warrior.