Using the THREE alias makes things fail when trying to use three.js
with e.g. webpack which will assign some alias other than "THREE" to
the module.

WebGLPrograms: Moved boneTexture generation to WebGLRenderer. Fixes webgl_animation_skinning_morph. See #10754.

This improves performance by not continuously
allocating a function in renderObjects when
object.isImmediateRenderObject is false.