Separate VisualViewport layer tree creation from attachment.

third_party/WebKit/LayoutTests/FlagExpectations/enable-slimming-paint-v2

 # Expectations for slimming paint v2
 # See: https://docs.google.com/document/d/1QCM912Dr6u38DqyQqd7pxQxDy8FFOoWMMDq7uAXqKdA/view
 # We are focused on fast/, compositing/, and svg/ with all other directories skipped (for now).
 
 Bug(none) accessibility/ [ Skip ]
 Bug(none) animations/ [ Skip ]
 Bug(none) app_banner/ [ Skip ]
 Bug(none) battery-status/ [ Skip ]
 Bug(none) bindings/ [ Skip ]
 Bug(none) bluetooth/ [ Skip ]
@@ skipping 431 matching lines @@
 Bug(none) compositing/squashing/squash-transform.html [ Failure ]
 Bug(none) compositing/squashing/squashed-repaints.html [ Failure ]
 Bug(none) compositing/squashing/squashing-inside-perspective.html [ Failure ]
 Bug(none) compositing/squashing/squashing-sparsity-heuristic.html [ Failure ]
 Bug(none) compositing/tiled-layers-hidpi.html [ Failure ]
 Bug(none) compositing/update-paint-phases.html [ Failure ]
 Bug(none) compositing/video/video-poster.html [ Crash Failure ]
 Bug(none) compositing/video/video-reflection.html [ Crash Failure  ]
 Bug(none) compositing/visibility/layer-visible-content.html [ Failure ]
 Bug(none) compositing/visibility/overlays-persist-on-navigation.html [ Crash ]
-Bug(none) compositing/visibility/overlays.html [ Crash ]
+Bug(none) compositing/visibility/overlays.html [ Failure Crash ]
 Bug(none) compositing/visibility/visibility-image-layers-dynamic.html [ Crash Failure ]
 Bug(none) compositing/visibility/visibility-image-layers.html [ Failure ]
 Bug(none) compositing/visibility/visibility-simple-video-layer.html [ Failure ]
 Bug(none) compositing/webgl/webgl-reflection.html [ Failure ]
 Bug(none) compositing/webgl/webgl-with-accelerated-background-color.html [ Failure ]
 Bug(none) compositing/will-change/composited-layers.html [ Failure ]
 Bug(none) fast/backgrounds/animated-svg-as-mask.html [ Failure ]
 Bug(none) fast/backgrounds/background-inherit-color-bug.html [ Failure ]
 Bug(none) fast/backgrounds/background-leakage-transforms.html [ Failure ]
 Bug(none) fast/backgrounds/mask-box-image.html [ Failure ]
@@ skipping 125 matching lines @@
 Bug(none) fast/events/platform-wheelevent-paging-xy-in-scrolling-page.html [ Failure ]
 Bug(none) fast/events/platform-wheelevent-paging-y-in-scrolling-page.html [ Failure ]
 Bug(none) fast/events/reveal-link-when-focused.html [ Failure ]
 Bug(none) fast/events/scale-and-scroll-body.html [ Crash Timeout ]
 Bug(none) fast/events/scale-and-scroll-iframe-body.html [ Crash Timeout ]
 Bug(none) fast/events/scale-and-scroll-iframe-window.html [ Crash Timeout ]
 Bug(none) fast/events/scale-and-scroll-window.html [ Crash Timeout ]
 Bug(none) fast/events/scroll-after-click-on-tab-index.html [ Failure ]
 Bug(none) fast/events/space-scroll-textinput-canceled.html [ Failure ]
 Bug(none) fast/events/touch/compositor-touch-hit-rects-animation.html [ Failure ]
-Bug(none) fast/events/touch/compositor-touch-hit-rects-global.html [ Crash ]
+Bug(none) fast/events/touch/compositor-touch-hit-rects-global.html [ Failure Crash ]
 Bug(none) fast/events/touch/compositor-touch-hit-rects-many.html [ Failure ]
 Bug(none) fast/events/touch/compositor-touch-hit-rects-non-composited-scroll.html [ Failure ]
 Bug(none) fast/events/touch/compositor-touch-hit-rects-scroll.html [ Failure ]
 Bug(none) fast/events/touch/compositor-touch-hit-rects-squashing.html [ Failure ]
 Bug(none) fast/events/touch/compositor-touch-hit-rects-trigger-commit.html [ Failure ]
 Bug(none) fast/events/touch/compositor-touch-hit-rects-transform-changed-nolayout.html [ Failure ]
 Bug(none) fast/events/touch/compositor-touch-hit-rects.html [ Failure ]
 Bug(none) fast/events/touch/gesture/gesture-scroll-by-page.html [ Failure ]
 Bug(none) fast/events/touch/gesture/gesture-scroll-by-pixel.html [ Failure ]
 Bug(none) fast/events/touch/touch-handler-assert-input-range.html [ Failure ]
@@ skipping 972 matching lines @@
 crbug.com/589265 compositing/masks/masked-ancestor.html [ Failure ]
 crbug.com/589265 compositing/masks/multiple-masks.html [ Failure ]
 crbug.com/589265 compositing/masks/simple-composited-mask.html [ Failure ]
 
 # Interesting one. The expectation contains an artifact due to incorrect
 # Skia peephole optimization.
 crbug.com/675805 fast/text/complex-text-opacity.html [ Failure ]
 
 # Failures due to frame scrollbars not painted
 crbug.com/589279 css3/blending/background-blend-mode-data-uri-svg-image.html [ Failure ]
- 
+
 # Need to write SPv2 version of this code.
 crbug.com/157218 compositing/overflow/border-radius-styles-with-composited-child.html [ Failure ]
 crbug.com/157218 compositing/overflow/siblings-with-border-radius-ancestor.html [ Failure ]
 crbug.com/157218 compositing/overflow/siblings-composited-with-border-radius-ancestor.html [ Failure ]
 crbug.com/157218 compositing/overflow/grandchild-composited-with-border-radius-ancestor.html [ Failure ]
 crbug.com/157218 compositing/overflow/grandchild-with-border-radius-ancestor.html [ Failure ]
 crbug.com/157218 compositing/overflow/siblings-composited-with-border-radius-ancestor-one-clipped.html [ Failure ]
 
 # Notes about rebaselined tests:
 #
@@ skipping 36 matching lines @@
 crbug.com/686897 virtual/threaded/fast/compositorworker/compositor-proxy-disconnect-worker.html [ Timeout ]
 crbug.com/686897 virtual/threaded/fast/compositorworker/visual-update.html [ Timeout ]
 crbug.com/686897 virtual/threaded/fast/compositorworker/basic-plumbing-main-to-worker.html [ Crash Failure Timeout ]
 crbug.com/686897 virtual/threaded/fast/compositorworker/basic-plumbing-worker-to-main.html [ Crash Failure Timeout ]
 
 # virtual/threaded variants of sub-directories and tests already skipped or marked as failing above.
 Bug(none) virtual/threaded/inspector/ [ Skip ]
 Bug(none) virtual/threaded/fast/scroll-behavior/ [ Skip ]
 Bug(none) virtual/threaded/compositing/visibility/layer-visible-content.html [ Failure ]
 Bug(none) virtual/threaded/compositing/visibility/overlays-persist-on-navigation.html [ Crash ]
-Bug(none) virtual/threaded/compositing/visibility/overlays.html [ Crash ]
+Bug(none) virtual/threaded/compositing/visibility/overlays.html [ Failure Crash ]
 Bug(none) virtual/threaded/compositing/visibility/visibility-image-layers-dynamic.html [ Crash Failure ]
 Bug(none) virtual/threaded/compositing/visibility/visibility-image-layers.html [ Failure ]
 Bug(none) virtual/threaded/compositing/visibility/visibility-simple-video-layer.html [ Failure ]
 Bug(none) virtual/threaded/compositing/webgl/webgl-reflection.html [ Failure ]
 Bug(none) virtual/threaded/printing/ [ Skip ]