CC Animation: Erase old animation system.
Basically, specialize all the code as if:
- use_compositor_animation_timelines is always true.
- Layer::layer_animation_controller_ is always nullptr.
- LayerImpl::layer_animation_controller_ is always nullptr.
- LayerTreeHost::animation_registrar_ is always nullptr.
- LayerTreeHostImpl::animation_registrar_ is always nullptr.
Next CL: Erase cc::LayerSettings everywhere.
BUG=575041
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
Review URL: https://codereview.chromium.org/1782433002
Cr-Commit-Position: refs/heads/master@{#380576}
22 files changed
