Make Lookdev works with bloom and TAA by rendering it before TAA and fixing
the motion vectors of the lookdev balls.
Rework Lookdev to remove much of its complexity. Use simpler matrices with
more understandable setup code.
Apply clang format as proposed in T53211.
For details on usage and instructions for migrating branches
without conflicts, see:
https://wiki.blender.org/wiki/Tools/ClangFormat
This pass create a velocity buffer which is basically a 2D motion vector
texture. This is not yet used for rendering but will be usefull for motion
blur and temporal reprojection.