Add back enable-blink-features=SlimmingPaintInvalidation

third_party/WebKit/LayoutTests/FlagExpectations/enable-blink-features=SlimmingPaintInvalidation

+# Expectations for slimmingPaintInvalidation feature
+
+# Different clipping behavior, sometimes more accurate (e.g. about css clip),
+# sometimes less accurate (e.g. when clip has transforms). This doesn't matter.
+Bug(none) paint/invalidation/outline-clip-change.html [ NeedsRebaseline ]
+Bug(none) paint/invalidation/scroll-in-transformed-layer.html [ NeedsRebaseline ]
+Bug(none) paint/invalidation/scroll-with-transformed-parent-layer.html [ NeedsRebaseline ]
+Bug(none) paint/invalidation/shift-relative-positioned-container-with-image-addition.html [ NeedsRebaseline ]
+
+crbug.com/648274 fast/multicol/span/abspos-containing-block-outside-spanner.html [ Failure ]
+
+# Missing enclosingIntRect for scale transforms.
+crbug.com/648769 paint/invalidation/invalidation-with-scale-transform.html [ Failure ]
+crbug.com/648769 paint/invalidation/transform-inline-layered-child.html [ Failure ]
+crbug.com/648769 paint/invalidation/transform-layout-repaint.html [ Failure ]
+crbug.com/648769 fast/sub-pixel/sub-pixel-accumulates-to-layers.html [ Failure ]
+
+# We use FrameView::x() and FrameView::y() which are integers to generate FrameView
+# preTranslation, but the old path uses offsets in the layout tree. Not sure if it's
+# a bug of the new path or the old path.
+Bug(none) paint/invalidation/repaint-during-scroll-with-zoom.html [ Failure ]
+
+# Missing SVG transform enclosingIntRect.
+crbug.com/651521 paint/invalidation/svg/absolute-sized-document-no-scrollbars.svg [ Failure ]
+crbug.com/651521 paint/invalidation/svg/tabgroup.svg [ Failure ]
+crbug.com/651521 paint/invalidation/svg/window.svg [ Failure ]
+crbug.com/651521 paint/invalidation/svg/animated-path-inside-transformed-html.xhtml [ Failure ]
+crbug.com/651521 paint/invalidation/svg/js-late-gradient-and-object-creation.svg [ Failure ]
+crbug.com/651521 paint/invalidation/svg/js-late-pattern-and-object-creation.svg [ Failure ]