All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=811449

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=0cab231345e9ff90501ada098dbb9c503052d2048d9b6217f21181e94fb5329f


Bot(s) for this bug's original alert(s):

android-nexus6
android-one
chromium-rel-win7-dual

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/14972ff5840000

📍 Found a significant difference after 1 commit.
https://pinpoint-dot-chromeperf.appspot.com/job/14972ff5840000

Don't composite trivial 3D on low-end devices. by chrishtr@chromium.org
https://chromium.googlesource.com/chromium/src/+/812a74e7bc08bf89f8d8dd6b2260492e4bc318b7

Understanding performance regressions:
  http://g.co/ChromePerformanceRegressions

The change in frame_times/css_value_type_transform_complex.html?api_css_animations_N_0316 is probably because of the overhead of checking
for a non-trivial animation on so many transform objects. I think this is
a pathological case, so going to ignore it.

Same goes for the rest of the cases.

I think I have a way to get back this performance, trying now.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ff4066808ef95efb35430d062ae6ad2705ca1ac6

commit ff4066808ef95efb35430d062ae6ad2705ca1ac6
Author: Chris Harrelson <chrishtr@chromium.org>
Date: Thu Mar 01 03:43:56 2018

[Go] Skip updating compositing reasons if style has not changed.

Bug:  811449 
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
Change-Id: I261236e488d36e1e575c0ad74450d3431ce34984
Reviewed-on: https://chromium-review.googlesource.com/924691
Commit-Queue: Chris Harrelson <chrishtr@chromium.org>
Reviewed-by: vmpstr <vmpstr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#540025}
[modify] https://crrev.com/ff4066808ef95efb35430d062ae6ad2705ca1ac6/third_party/WebKit/Source/core/layout/LayoutObject.cpp
[modify] https://crrev.com/ff4066808ef95efb35430d062ae6ad2705ca1ac6/third_party/WebKit/Source/core/paint/PaintLayer.cpp
[modify] https://crrev.com/ff4066808ef95efb35430d062ae6ad2705ca1ac6/third_party/WebKit/Source/core/paint/PaintLayer.h
[modify] https://crrev.com/ff4066808ef95efb35430d062ae6ad2705ca1ac6/third_party/WebKit/Source/core/paint/compositing/PaintLayerCompositor.cpp
[modify] https://crrev.com/ff4066808ef95efb35430d062ae6ad2705ca1ac6/third_party/WebKit/Source/core/paint/compositing/PaintLayerCompositor.h
[modify] https://crrev.com/ff4066808ef95efb35430d062ae6ad2705ca1ac6/third_party/WebKit/Source/core/style/ComputedStyle.cpp
[modify] https://crrev.com/ff4066808ef95efb35430d062ae6ad2705ca1ac6/third_party/WebKit/Source/core/style/ComputedStyle.h
[modify] https://crrev.com/ff4066808ef95efb35430d062ae6ad2705ca1ac6/third_party/WebKit/Source/core/style/ComputedStyleTest.cpp
[modify] https://crrev.com/ff4066808ef95efb35430d062ae6ad2705ca1ac6/third_party/WebKit/Source/core/style/StyleDifference.h