Even after the latest update, Syllabear's Battle Cry will not apply to summons of his created by his spirit bear
For example, if your spirit bear cast a necronomicon, or gets an illusion rune, or uses manta style- those minions won't get the battle cry bonus when cast
Whereas the same summons, if they were created by sylla himself, will get the effect

In DotA 1, it applied to all summons under your control