SPv2: Limit compositor element id application to a single layer.

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) app_banner/ [ Skip ]
 Bug(none) battery-status/ [ Skip ]
 Bug(none) bindings/ [ Skip ]
 Bug(none) bluetooth/ [ Skip ]
 Bug(none) canvas/ [ Skip ]
@@ skipping 1341 matching lines @@
 crbug.com/589265 fast/sub-pixel/sub-pixel-transparency-layer.html [ Failure ]
 crbug.com/589265 images/color-profile-layer-filter.html [ Failure Crash ]
 crbug.com/589265 svg/custom/non-opaque-filters.svg [ Failure ]
 crbug.com/589265 svg/custom/root-container-opacity-clip-viewBox.svg [ Failure ]
 crbug.com/589265 svg/foreignObject/filter.html [ Failure ]
 crbug.com/589265 svg/text/text-layout-crash.html [ Failure ]
 crbug.com/589265 virtual/threaded/animations/animated-filter-svg-element.html [ Failure Crash ]
 
 # Some work remains to fully support composited animation and scrolling.
 Bug(none) virtual/threaded/animations/composited-animation-style-update.html [ Failure ]
-crbug.com/702350 transitions/opacity-transform-transitions-inside-iframe.html [ Timeout Crash ]
-crbug.com/702350 virtual/threaded/transitions/opacity-transform-transitions-inside-iframe.html [ Timeout Crash ]
+crbug.com/702350 transitions/opacity-transform-transitions-inside-iframe.html [ Timeout ]
+crbug.com/702350 virtual/threaded/transitions/opacity-transform-transitions-inside-iframe.html [ Timeout ]
 crbug.com/702353 transitions/transition-end-event-destroy-iframe.html [ Timeout ]
 crbug.com/702353 virtual/threaded/transitions/transition-end-event-destroy-iframe.html [ Timeout ]
 crbug.com/702353 virtual/threaded/transitions/extra-transition.html [ Timeout ]
 crbug.com/702365 virtual/threaded/animations/composited-filter-webkit-filter.html [ Failure ]
 crbug.com/702370 virtual/threaded/animations/compositor-independent-transform-cancel.html [ Failure ]
 crbug.com/702379 virtual/threaded/animations/skew-notsequential-compositor.html [ Failure ]
 crbug.com/692310 virtual/threaded/animations/3d/replace-filling-transform.html [ Crash ]
 crbug.com/692310 virtual/threaded/animations/change-transform-style-during-animation.html [ Crash ]
 crbug.com/692310 virtual/threaded/animations/fill-mode-transform.html [ Crash ]
 # Eight of the frames in the test below paint no content. In SPv2 we will never
@@ skipping 31 matching lines @@
 Bug(700530) fast/css/background-clip-values.html [ Failure ]
 Bug(700530) svg/text/small-fonts-in-html5.html [ Failure ]
 Bug(700530) compositing/overflow/paint-neg-z-order-descendants-into-scrolling-contents-layer.html [ Failure ]
 Bug(700530) fast/multicol/tall-content-in-inner-with-fixed-height.html [ Failure ]
 Bug(700530) compositing/geometry/abs-position-inside-opacity.html [ Failure ]
 Bug(700530) fast/css3-text/css3-text-decoration/text-underline-position/text-underline-position-cjk.html [ Failure ]
 
 # The following debug crashes have not been triaged.
 crbug.com/702805 css3/blending/svg-isolation-add-masking.html [ Crash ]
 crbug.com/702805 css3/blending/svg-blend-layer-filter.html [ Crash ]
-crbug.com/702805 virtual/threaded/transitions/opacity-transition-zindex.html [ Crash ]
 crbug.com/702805 virtual/threaded/compositing/visibility/overlays-persist-on-navigation.html [ Crash ]
 crbug.com/702805 virtual/threaded/animations/responsive-neutral-keyframe.html [ Crash ]
-crbug.com/702805 virtual/threaded/animations/timing-functions.html [ Crash ]
-crbug.com/702805 virtual/threaded/animations/animation-offscreen-to-onscreen.html [ Crash ]
-crbug.com/702805 virtual/threaded/animations/3d/matrix-transform-type-animation.html [ Crash ]
-crbug.com/702805 virtual/threaded/animations/viewport-unit-animation-responsive.html [ Crash ]
-crbug.com/702805 virtual/threaded/animations/composited-animation-independent-transform-cancel.html [ Crash ]
 crbug.com/702805 svg/text/removing-id-on-path.html [ Failure ]
 crbug.com/702805 svg/text/selection-style-within-mask-crash.html [ Crash ]
 crbug.com/702805 svg/custom/mask-with-all-units.svg [ Crash ]
 crbug.com/702805 svg/custom/pattern-directly-and-indirectly-referenced.svg [ Crash ]
 crbug.com/702805 svg/custom/circular-clip-path-references-crash.svg [ Crash ]
 crbug.com/702805 svg/custom/mask-excessive-malloc.svg [ Crash ]
 crbug.com/702805 svg/custom/resources-css-scaled.html [ Crash ]
 crbug.com/702805 svg/custom/mask-with-default-value.svg [ Crash ]
 crbug.com/702805 svg/custom/viewport-resource-inval.svg [ Crash ]
 crbug.com/702805 svg/custom/transformedMaskFails.svg [ Crash ]
 crbug.com/702805 svg/custom/visibility-enable-on-svg-element-contained-border-radius.html [ Crash ]
 crbug.com/702805 svg/custom/mask-on-multiple-objects.svg [ Crash ]
 crbug.com/702805 svg/filters/feImage-self-referencing.html [ Crash ]
 crbug.com/702805 svg/filters/feImage-self-and-other-referencing.html [ Crash ]
 crbug.com/702805 svg/filters/feSpecularLight-premultiplied.svg [ Crash ]
 crbug.com/702805 svg/masking/mask-with-visibility-hidden-group.html [ Crash ]
 crbug.com/702805 svg/masking/mask-type-alpha.svg [ Crash ]
 crbug.com/702805 svg/masking/mask-type-not-set.svg [ Crash ]
 crbug.com/702805 svg/masking/mask-type-luminance.svg [ Crash ]
 crbug.com/702805 svg/hixie/perf/006.xml [ Crash ]
 crbug.com/702805 svg/hixie/perf/003.xml [ Crash ]
 crbug.com/702805 svg/hixie/perf/001.xml [ Crash ]
 crbug.com/702805 svg/hixie/perf/005.xml [ Crash ]
 crbug.com/702805 svg/hixie/perf/002.xml [ Crash ]
 crbug.com/702805 svg/hixie/perf/004.xml [ Crash ]
 crbug.com/702805 animations/responsive-neutral-keyframe.html [ Crash ]
-crbug.com/702805 animations/animation-offscreen-to-onscreen.html [ Crash ]
-crbug.com/702805 animations/timing-functions.html [ Crash ]
-crbug.com/702805 animations/viewport-unit-animation-responsive.html [ Crash ]
-crbug.com/702805 animations/3d/matrix-transform-type-animation.html [ Crash ]
 crbug.com/702805 fast/loader/scroll-restore-target-pseudo.html [ Crash ]
 crbug.com/702805 fast/loader/scroll-restore-overrides-fragment.html [ Crash ]
 crbug.com/702805 fast/forms/select-popup/popup-menu-appearance-coarse.html [ Crash Timeout ]
 crbug.com/702805 css3/blending/svg-blend-layer-mask.html [ Crash ]
 crbug.com/702805 fast/borders/border-radius-mask-video-crash.html [ Crash ]
 crbug.com/702805 fast/css/getComputedStyle/invalid-url-double-recalc-serialization.html [ Crash ]
 crbug.com/702805 fast/overflow/overflow-update-transform.html [ Crash ]
 crbug.com/702805 web-animations-api/element-animate-list-of-keyframes.html [ Crash ]
 crbug.com/702805 web-animations-api/animation-reverse-end-exclusive.html [ Crash ]
 crbug.com/702805 compositing/transitions/singular-scale-transition.html [ Crash ]
 crbug.com/702805 compositing/images/direct-image-dynamic-border-radius.html [ Crash ]
 crbug.com/702805 compositing/content-changed-chicken-egg.html [ Crash ]
 crbug.com/702805 compositing/squashing/remove-from-grouped-mapping-on-reassignment.html [ Crash ]
 crbug.com/702805 compositing/visibility/overlays-persist-on-navigation.html [ Crash ]
 crbug.com/702805 compositing/overflow/overflow-positioning.html [ Crash ]
 crbug.com/702805 compositing/layer-creation/incremental-destruction.html [ Crash ]
-crbug.com/702805 transitions/opacity-transition-zindex.html [ Crash ]
 crbug.com/702805 fast/forms/number/number-stepup-stepdown-from-renderer.html [ Crash Timeout ]
 crbug.com/702805 fast/forms/range/range-stepup-stepdown-from-renderer.html [ Crash Timeout ]
 crbug.com/702805 fast/dom/shadow/selections-in-shadow.html [ Crash Timeout ]