[CompositeAfterPaint] Fix backdrop-filters

- Force compositing for backdrop-filters. We probably won't support
  non-composited backdrop-filters because it depends on viz renderers.

- Paint empty display item for backdrop-filter to ensure a paint
  chunk which will create the composited backdrop-filter layer.

Bug: 923429
Change-Id: Ib2afbde2c4ad3a485049b25ee63d6537f675ade6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1824317
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Reviewed-by: Mason Freed <masonfreed@chromium.org>
Cr-Commit-Position: refs/heads/master@{#700376}

third_party/blink/renderer/core/paint/compositing/compositing_reason_finder.cc

@@ -139,6 +139,9 @@ CompositingReasons CompositingReasonFinder::DirectReasonsForPaintProperties(
   if (RequiresCompositingForScrollDependentPosition(*layer))
     reasons |= CompositingReason::kScrollDependentPosition;
 
+  if (style.HasBackdropFilter())
+    reasons |= CompositingReason::kBackdropFilter;
+
   return reasons;
 }
 

third_party/blink/renderer/core/paint/paint_layer_painter.cc

@@ -538,13 +538,18 @@ PaintResult PaintLayerPainter::PaintLayerContents(
                                    local_painting_info, paint_flags);
     }
 
-    if (!is_painting_overlay_scrollbars && paint_layer_.PaintsWithFilters() &&
+    if (!is_painting_overlay_scrollbars) {
+      // For filters, if the layer painted nothing, we need to issue a no-op
+      // display item to ensure the filters won't be ignored. For backdrop
+      // filters, we issue the display item regardless of other paintings to
+      // ensure correct bounds of the composited layer for the backdrop filter.
+      if ((paint_layer_.PaintsWithFilters() &&
            display_item_list_size_before_painting ==
-            context.GetPaintController().NewDisplayItemList().size()) {
-      // If a layer with filters painted nothing, we need to issue a no-op
-      // display item to ensure the filters won't be ignored.
+               context.GetPaintController().NewDisplayItemList().size()) ||
+          paint_layer_.GetLayoutObject().HasBackdropFilter()) {
         PaintEmptyContentForFilters(context);
       }
+    }
   }  // FilterPainter block
 
   bool should_paint_mask = is_painting_mask && should_paint_content &&
@@ -879,7 +884,8 @@ void PaintLayerPainter::FillMaskingFragment(GraphicsContext& context,
 // Generate a no-op DrawingDisplayItem to ensure a non-empty chunk for the
 // filter without content.
 void PaintLayerPainter::PaintEmptyContentForFilters(GraphicsContext& context) {
-  DCHECK(paint_layer_.PaintsWithFilters());
+  DCHECK(paint_layer_.PaintsWithFilters() ||
+         paint_layer_.GetLayoutObject().HasBackdropFilter());
 
   ScopedPaintChunkProperties paint_chunk_properties(
       context.GetPaintController(),

third_party/blink/renderer/platform/graphics/compositing_reasons.h

@@ -159,7 +159,7 @@ class PLATFORM_EXPORT CompositingReason {
         kPerspectiveWith3DDescendants | kPreserve3DWith3DDescendants |
         kActiveTransformAnimation,
     kDirectReasonsForEffectProperty = kActiveOpacityAnimation |
-                                      kWillChangeOpacity |
+                                      kWillChangeOpacity | kBackdropFilter |
                                       kActiveBackdropFilterAnimation,
     kDirectReasonsForFilterProperty = kActiveFilterAnimation,
   };

third_party/blink/web_tests/FlagExpectations/enable-blink-features=CompositeAfterPaint

@@ -138,9 +138,6 @@ crbug.com/959941 virtual/threaded/fast/scrolling/mouse-scrolling-over-standard-s
 
 crbug.com/907601 virtual/threaded/fast/scrolling/events/scrollend-event-fired-after-snap.html [ Skip ]
 
-# Single pixel difference around one of the radiused borders.
-Bug(none) external/wpt/css/filter-effects/backdrop-filter-reference-filter.html [ Failure ]
-
 # Scrolling with the mouse wheel does not work.
 crbug.com/979352 virtual/threaded/fast/scrolling/non-composited-scroller-in-scrolled-absolute-scroller.html [ Failure ]
 crbug.com/979352 virtual/threaded/fast/scrolling/non-composited-scroller-in-scrolled-position-fixed-scroller.html [ Failure ]
@@ -375,68 +372,10 @@ crbug.com/909749 fast/events/touch/compositor-touch-hit-rects-global.html [ Fail
 crbug.com/909749 fast/events/touch/compositor-touch-hit-rects-non-composited-scroll.html [ Failure ]
 
 # Backdrop filter
-crbug.com/923429 compositing/layer-creation/fixed-position-out-of-view-with-backdrop-filter.html [ Failure ]
-crbug.com/923429 css3/filters/backdrop-filter-basic-blur.html [ Timeout Failure ]
-crbug.com/923429 css3/filters/backdrop-filter-boundary.html [ Failure ]
-crbug.com/923429 css3/filters/backdrop-filter-browser-zoom.html [ Failure ]
-crbug.com/923429 css3/filters/backdrop-filter-border-radius.html [ Failure ]
-crbug.com/923429 css3/filters/backdrop-filter-clip-rect-zoom.html [ Failure ]
-crbug.com/923429 css3/filters/backdrop-filter-edge-clipping-2.html [ Failure ]
-crbug.com/923429 css3/filters/backdrop-filter-rendering.html [ Failure ]
-crbug.com/923429 css3/filters/backdrop-filter-rendering-no-background.html [ Failure ]
-crbug.com/923429 css3/filters/backdrop-filter-transform.html [ Failure ]
-crbug.com/923429 css3/filters/backdrop-filter-edge-pixels.html [ Failure ]
-crbug.com/923429 css3/filters/backdrop-filter-clip-radius-zoom.html [ Failure ]
 crbug.com/923429 css3/filters/backdrop-filter-plus-mask.html [ Failure ]
 crbug.com/923429 css3/filters/backdrop-filter-plus-mask-large.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filter-basic-background-color.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filter-basic-opacity-2.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filter-basic.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filter-clip-rect.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filter-fixed-clip.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filter-isolation.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filter-isolation-fixed.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filter-isolation-isolate.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filter-update.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filter-clipped.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filter-plus-filter.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filters-brightness.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filters-contrast.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filters-grayscale.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filters-hue-rotate.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filters-invert.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filters-saturate.html [ Failure ]
-crbug.com/923429 external/wpt/css/filter-effects/backdrop-filters-sepia.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-basic-blur.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-border-radius.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-boundary.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-browser-zoom.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-clip-rect-zoom.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-edge-pixels.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-rendering-no-background.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-rendering.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-transform.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-clip-radius-zoom.html [ Failure ]
 crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-plus-mask.html [ Failure ]
 crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-plus-mask-large.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filter-basic-background-color.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filter-basic-opacity-2.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filter-basic.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filter-clipped.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filter-fixed-clip.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filter-isolation-fixed.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filter-isolation-isolate.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filter-isolation.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filter-update.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filter-plus-filter.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filters-brightness.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filters-contrast.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filters-grayscale.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filters-hue-rotate.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filters-invert.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filters-saturate.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/external/wpt/css/filter-effects/backdrop-filters-sepia.html [ Failure ]
-crbug.com/923429 virtual/scalefactor200/css3/filters/backdrop-filter-edge-clipping-2.html [ Failure ]
 
 crbug.com/940033 virtual/threaded/fast/scrolling/wheel-scrolling-over-custom-scrollbar.html [ Failure ]
 

third_party/blink/web_tests/flag-specific/enable-blink-features=CompositeAfterPaint/compositing/layer-creation/fixed-position-out-of-view-with-backdrop-filter-expected.txt

+{
+  "layers": [
+    {
+      "name": "Scrolling background of LayoutView #document",
+      "bounds": [785, 1021],
+      "contentsOpaque": true,
+      "backgroundColor": "#FFFFFF"
+    },
+    {
+      "name": "VerticalScrollbar",
+      "position": [785, 0],
+      "bounds": [15, 600]
+    },
+    {
+      "name": "LayoutNGBlockFlow (positioned) DIV class='fixed'",
+      "bounds": [10, 10],
+      "transform": 1
+    },
+    {
+      "name": "LayoutNGBlockFlow (positioned) DIV class='fixed'",
+      "bounds": [10, 10],
+      "transform": 2
+    },
+    {
+      "name": "LayoutNGBlockFlow (positioned) DIV class='fixed'",
+      "bounds": [10, 10],
+      "transform": 3
+    },
+    {
+      "name": "LayoutNGBlockFlow (positioned) DIV class='fixed'",
+      "bounds": [10, 10]
+    }
+  ],
+  "transforms": [
+    {
+      "id": 1,
+      "transform": [
+        [1, 0, 0, 0],
+        [0, 1, 0, 0],
+        [0, 0, 1, 0],
+        [8, 1013, 0, 1]
+      ]
+    },
+    {
+      "id": 2,
+      "transform": [
+        [1, 0, 0, 0],
+        [0, 1, 0, 0],
+        [0, 0, 1, 0],
+        [8, -100, 0, 1]
+      ]
+    },
+    {
+      "id": 3,
+      "transform": [
+        [1, 0, 0, 0],
+        [0, 1, 0, 0],
+        [0, 0, 1, 0],
+        [1000, 0, 0, 1]
+      ]
+    }
+  ]
+}
+