The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6ccbc7d47b41c05863cce3c0762d21dd406316c7

commit 6ccbc7d47b41c05863cce3c0762d21dd406316c7
Author: jbroman <jbroman@chromium.org>
Date: Wed Jul 27 04:45:41 2016

Use surface copy requests for layout tests.

This replaces the CopyOutputRequest on the root layer in
RenderWidgetCompositor::compositeAndReadbackAsync with one on the cc::Surface.
This allows Blink to remain ignorant of copy requests, even in
Slimming Paint v2, when it builds its own property trees (where copy requests
are passed today).

BUG= 630691 
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_blink_rel,mac_blink_rel,win_blink_rel

Review-Url: https://codereview.chromium.org/2162083005
Cr-Commit-Position: refs/heads/master@{#408043}

[modify] https://crrev.com/6ccbc7d47b41c05863cce3c0762d21dd406316c7/cc/test/test_delegating_output_surface.cc
[modify] https://crrev.com/6ccbc7d47b41c05863cce3c0762d21dd406316c7/cc/test/test_delegating_output_surface.h
[modify] https://crrev.com/6ccbc7d47b41c05863cce3c0762d21dd406316c7/content/renderer/gpu/render_widget_compositor.cc
[modify] https://crrev.com/6ccbc7d47b41c05863cce3c0762d21dd406316c7/content/renderer/gpu/render_widget_compositor.h
[modify] https://crrev.com/6ccbc7d47b41c05863cce3c0762d21dd406316c7/content/renderer/gpu/render_widget_compositor_delegate.h
[modify] https://crrev.com/6ccbc7d47b41c05863cce3c0762d21dd406316c7/content/renderer/gpu/render_widget_compositor_unittest.cc
[modify] https://crrev.com/6ccbc7d47b41c05863cce3c0762d21dd406316c7/content/renderer/layout_test_dependencies.h
[modify] https://crrev.com/6ccbc7d47b41c05863cce3c0762d21dd406316c7/content/renderer/render_thread_impl.cc
[modify] https://crrev.com/6ccbc7d47b41c05863cce3c0762d21dd406316c7/content/renderer/render_thread_impl.h
[modify] https://crrev.com/6ccbc7d47b41c05863cce3c0762d21dd406316c7/content/renderer/render_widget.cc
[modify] https://crrev.com/6ccbc7d47b41c05863cce3c0762d21dd406316c7/content/renderer/render_widget.h
[modify] https://crrev.com/6ccbc7d47b41c05863cce3c0762d21dd406316c7/content/test/layouttest_support.cc

OK, so layout tests are now runnable with "--additional-drt-flag=--enable-slimming-paint-v2 --additional-drt-flag=--enable-layer-lists". There are, however, new failures.

Most of them look to be subpixel differences (possibly due to LCD text?). Reassigning to pdr to look further. After that, we can make --enable-slimming-paint-v2 imply --enable-layer-lists. This is one CL that ought to do the trick:

https://codereview.chromium.org/2152133002

Beside LCD text, the subpixel differences are probably due to the differences in compositing order. e.g. whether to create render surfaces for clip / effect. That is, subject to change as layerization matures and safe to ignore.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a8c172dd5a67c388bb3cd693a8d60e7d3565f2aa

commit a8c172dd5a67c388bb3cd693a8d60e7d3565f2aa
Author: pdr <pdr@chromium.org>
Date: Tue Aug 09 18:17:39 2016

Basic support for backface visibility in spv2 with --layer-lists

This patch adds support for backface visibility in spv2 with layer
lists. With this patch, all svp2 backface visibility tests pass (and
two new ones too) when tests are run with the following flags:
--additional-driver-flag=--enable-slimming-paint-v2
--additional-driver-flag=--enable-layer-lists

Test expectations will be updated in a followup when layer list mode
is switched to be the default.

BUG= 587236 , 630691 

Review-Url: https://codereview.chromium.org/2205783002
Cr-Commit-Position: refs/heads/master@{#410746}

[modify] https://crrev.com/a8c172dd5a67c388bb3cd693a8d60e7d3565f2aa/third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.cpp

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4cd50edf73839959f775daa562e209d3802dd64f

commit 4cd50edf73839959f775daa562e209d3802dd64f
Author: pdr <pdr@chromium.org>
Date: Wed Aug 31 00:17:08 2016

Make --enable-slimming-paint-v2 enable --enable-layer-lists

With this patch, enabling SlimmingPaintV2 will automatically enable
enable-layer-lists.

CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
BUG= 630691 

Review-Url: https://codereview.chromium.org/2286343003
Cr-Commit-Position: refs/heads/master@{#415508}

[modify] https://crrev.com/4cd50edf73839959f775daa562e209d3802dd64f/content/browser/renderer_host/render_process_host_impl.cc
[modify] https://crrev.com/4cd50edf73839959f775daa562e209d3802dd64f/third_party/WebKit/LayoutTests/FlagExpectations/enable-slimming-paint-v2

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4111dba812f24996262b71c76dd98a7eecb8f71a

commit 4111dba812f24996262b71c76dd98a7eecb8f71a
Author: pdr <pdr@chromium.org>
Date: Mon Sep 05 02:57:39 2016

Remove non-layer-list codepath from PaintArtifactCompositor

Slimming paint v2 only uses layer lists now and the old non-layer-list
codepath can be removed.

BUG= 630691 
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2307143002
Cr-Commit-Position: refs/heads/master@{#416489}

[modify] https://crrev.com/4111dba812f24996262b71c76dd98a7eecb8f71a/third_party/WebKit/Source/core/paint/HTMLCanvasPainterTest.cpp
[modify] https://crrev.com/4111dba812f24996262b71c76dd98a7eecb8f71a/third_party/WebKit/Source/core/paint/StubChromeClientForSPv2.h
[modify] https://crrev.com/4111dba812f24996262b71c76dd98a7eecb8f71a/third_party/WebKit/Source/core/paint/VideoPainterTest.cpp
[modify] https://crrev.com/4111dba812f24996262b71c76dd98a7eecb8f71a/third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.cpp
[modify] https://crrev.com/4111dba812f24996262b71c76dd98a7eecb8f71a/third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.h
[modify] https://crrev.com/4111dba812f24996262b71c76dd98a7eecb8f71a/third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositorTest.cpp
[modify] https://crrev.com/4111dba812f24996262b71c76dd98a7eecb8f71a/third_party/WebKit/Source/platform/testing/WebLayerTreeViewImplForTesting.cpp
[modify] https://crrev.com/4111dba812f24996262b71c76dd98a7eecb8f71a/third_party/WebKit/Source/platform/testing/WebLayerTreeViewImplForTesting.h

I think we can call this fixed now. This migration raised one issue that's still unresolved (642401) but we have a plan in a dependent bug (557160).