The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/859ff15220fc4aaa7eaa985df879a6b1e39f73b8

commit 859ff15220fc4aaa7eaa985df879a6b1e39f73b8
Author: Yi Gu <yigu@chromium.org>
Date: Tue Oct 16 19:17:09 2018

[animation worklet] Drive group effects by their own local time

Currently all the effects of an animation are driven by the local time
of the first effect. Rather, they should be driven by the individual
local time.

This patch adds WorkletGroupEffectProxy to Animator and only initialize
it when necessary, i.e. animating group effects. Single effect animation
follows the existing logic which is not affected by this patch.

Bug:  894180 
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_layout_tests_slimming_paint_v2;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I24a828d5afd07d94854683744e5d765af45c82c8
Reviewed-on: https://chromium-review.googlesource.com/c/1274192
Reviewed-by: Stephen McGruer <smcgruer@chromium.org>
Reviewed-by: Jeremy Roman <jbroman@chromium.org>
Reviewed-by: Majid Valipour <majidvp@chromium.org>
Commit-Queue: Yi Gu <yigu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#600073}
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/cc/animation/animation_host_unittest.cc
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/cc/animation/worklet_animation.cc
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/cc/animation/worklet_animation_unittest.cc
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/cc/trees/layer_tree_mutator.cc
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/cc/trees/layer_tree_mutator.h
[add] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/WebKit/LayoutTests/animations/animationworklet/animate-multiple-effects-on-different-targets-via-main-thread-expected.txt
[rename] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/WebKit/LayoutTests/animations/animationworklet/animate-multiple-effects-on-different-targets-via-main-thread.html
[add] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/WebKit/LayoutTests/animations/animationworklet/multiple-effects-on-same-target-driven-by-individual-local-time-expected.txt
[copy] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/WebKit/LayoutTests/animations/animationworklet/multiple-effects-on-same-target-driven-by-individual-local-time.html
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/WebKit/LayoutTests/http/tests/origin_trials/webexposed/animationworklet-origin-trial-interfaces-worklet-scope-expected.txt
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/WebKit/LayoutTests/platform/android/http/tests/origin_trials/webexposed/animationworklet-origin-trial-interfaces-worklet-scope-expected.txt
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/modules/animationworklet/BUILD.gn
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/modules/animationworklet/animation_worklet_global_scope.cc
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/modules/animationworklet/animation_worklet_global_scope.h
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/modules/animationworklet/animation_worklet_global_scope_test.cc
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/modules/animationworklet/animator.cc
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/modules/animationworklet/animator.h
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/modules/animationworklet/worklet_animation.cc
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/modules/animationworklet/worklet_animation.h
[add] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/modules/animationworklet/worklet_group_effect_proxy.cc
[add] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/modules/animationworklet/worklet_group_effect_proxy.h
[add] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/modules/animationworklet/worklet_group_effect_proxy.idl
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/modules/modules_idl_files.gni
[modify] https://crrev.com/859ff15220fc4aaa7eaa985df879a6b1e39f73b8/third_party/blink/renderer/platform/graphics/animation_worklet_mutator_dispatcher_impl_test.cc