Blender Git Loki

Depsgraph: Use new scene update API in preview render

Depsgraph: Make graph to be per-scene-layer for RNA

New access is C.scene.render_layers.active.depsgraph. This will give depsgraph
for a given layer. In the future there will need to be some extra context to be
passed.

Depsgraph: Cleanup, remove depgraph_legacy from evaluation routines

Depsgraph: Cleanup, remove depsgraph_legacy from building routines

Depsgraph: Cleanup, remove unused function

Depsgraph: Cleanup, remove depsgraph_legacy from depsgraph_tag.cc

Depsgraph: Avoid non-requested allocation of depsgraph

Cycles: reduce closure memory usage for emission/shadow shader data.

With a Titan Xp, reduces path trace local memory from 1092MB to 840MB.
Benchmark performance was within 1% with both RX 480 and Titan Xp.

Original patch was implemented by Sergey.

Differential Revision: https://developer.blender.org/D2249

Code refactor: sum transparent and absorption weights outside closures.

Code refactor: remove emission and background closures, sum directly.

Cycles: fix inefficient attribute map storage, saves 615MB in victor scene.

Code refactor: device memory cleanups, preparing for mapped host memory.

Cycles: reserve CUDA local memory ahead of time.

This way we can log the amount of memory used, and it will be important
for host mapped memory support.

Merge branch 'master' into blender2.8

Cleanup: order buffer length after the buffer

Cleanup: remove paranoid NULL check

Cleanup: indentation, line wrapping

Cleanup: spelling

Fix broken macOS build with libsndfile, name is different than in master.

Tool System: Don't add duplicate keymap items