Temporarily disable text-on-opaque optimization

This is to evaluate the performance improvement of the optimization in
1 or 2 canary builds. Will revert after that.

This disables the optimization for composited scrolling added in
crrev.com/771292 (based on the LCD-text on opaque optimization added
in crrev.com/768555).

Bug: 1113269
Change-Id: I20250169241d8f6d99e9bd917974aaf3fd0f675a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2351400
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Reviewed-by: Philip Rogers <pdr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#797498}

third_party/blink/renderer/core/page/scrolling/main_thread_scrolling_reasons_test.cc

@@ -403,8 +403,8 @@ TEST_F(NonCompositedMainThreadScrollingReasonsTest, ClipTest) {
 }
 
 TEST_F(NonCompositedMainThreadScrollingReasonsTest, ClipPathTest) {
-  TestNonCompositedReasons("clip-path",
-                           cc::MainThreadScrollingReason::kNotScrollingOnMain);
+  TestNonCompositedReasons(
+      "clip-path", cc::MainThreadScrollingReason::kNotOpaqueForTextAndLCDText);
 }
 
 TEST_F(NonCompositedMainThreadScrollingReasonsTest, BoxShadowTest) {
@@ -424,8 +424,9 @@ TEST_F(NonCompositedMainThreadScrollingReasonsTest, StackingContextTest) {
 }
 
 TEST_F(NonCompositedMainThreadScrollingReasonsTest, BorderRadiusTest) {
-  TestNonCompositedReasons("border-radius",
-                           cc::MainThreadScrollingReason::kNotScrollingOnMain);
+  TestNonCompositedReasons(
+      "border-radius",
+      cc::MainThreadScrollingReason::kNotOpaqueForTextAndLCDText);
 }
 
 TEST_F(NonCompositedMainThreadScrollingReasonsTest,

third_party/blink/renderer/core/page/scrolling/scrolling_test.cc

@@ -1834,6 +1834,8 @@ TEST_P(UnifiedScrollingSimTest,
 // embedded in an iframe, by loading a document with an iframe that has a
 // scroller with an inset box shadow, and ensuring that scroller generates a
 // compositor scroll node with the proper noncomposited reasons set.
+// TODO(crbug.com/1113269): Temporarily disabled.
+#if 0
 TEST_P(UnifiedScrollingSimTest, ScrollNodeForEmbeddedScrollers) {
   SimRequest request("https://example.com/test.html", "text/html");
   LoadURL("https://example.com/test.html");
@@ -1914,6 +1916,7 @@ TEST_P(UnifiedScrollingSimTest, ScrollNodeForEmbeddedScrollers) {
                    ->property_trees()
                    ->scroll_tree.IsComposited(*child_scroll_node));
 }
+#endif
 
 // Similar to the above test, but for deeper nesting iframes to ensure we
 // generate scroll nodes that are deeper than the main frame's children.

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

@@ -2544,6 +2544,18 @@ bool PaintLayerScrollableArea::ComputeNeedsCompositedScrolling(
   return needs_composited_scrolling;
 }
 
+static bool IsOpaqueForLCDText(const PaintLayer& layer, const LayoutBox& box) {
+  if (RuntimeEnabledFeatures::CompositeAfterPaintEnabled())
+    return box.TextIsKnownToBeOnOpaqueBackground();
+
+  // TODO(crbug.com/1113269): TextIsKnownToBeOnOpaqueBackground() is temporarily
+  // replaced with BackgroundIsKnownToBeOpaqueInRect() to evaluate the
+  // performance improvement. Will restore after 1 or 2 canary builds.
+  DisableCompositingQueryAsserts disabler;
+  return layer.BackgroundIsKnownToBeOpaqueInRect(box.PhysicalPaddingBoxRect(),
+                                                 true);
+}
+
 bool PaintLayerScrollableArea::ComputeNeedsCompositedScrollingInternal(
     BackgroundPaintLocation background_paint_location_if_composited,
     bool force_prefer_compositing_to_lcd_text) {
@@ -2589,7 +2601,8 @@ bool PaintLayerScrollableArea::ComputeNeedsCompositedScrollingInternal(
           cc::MainThreadScrollingReason::kHasTransformAndLCDText;
       needs_composited_scrolling = false;
     }
-    if (!box->TextIsKnownToBeOnOpaqueBackground()) {
+
+    if (!IsOpaqueForLCDText(*layer_, *box)) {
       non_composited_main_thread_scrolling_reasons_ |=
           cc::MainThreadScrollingReason::kNotOpaqueForTextAndLCDText;
       needs_composited_scrolling = false;

third_party/blink/renderer/platform/graphics/graphics_layer.cc

@@ -565,7 +565,8 @@ void GraphicsLayer::SetContentsOpaque(bool opaque) {
 }
 
 void GraphicsLayer::SetContentsOpaqueForText(bool opaque) {
-  CcLayer().SetContentsOpaqueForText(opaque);
+  // TODO(crbug.com/1113269): Temporarily disable this optimization.
+  // CcLayer().SetContentsOpaqueForText(opaque);
 }
 
 void GraphicsLayer::SetHitTestable(bool should_hit_test) {

third_party/blink/web_tests/TestExpectations

@@ -118,6 +118,36 @@ crbug.com/759632 http/tests/devtools/network/network-datasaver-warning.js [ Fail
 #  display-lock
 # Some additional bugs that are caused by painting problems are also within this section.
 
+# TODO(crbug.com/1113629): Temporary disable these test for the experiment
+crbug.com/1113629 compositing/contents-opaque/overflow-hidden-child-layers.html [ Failure ]
+crbug.com/1113629 compositing/geometry/foreground-layer.html [ Failure ]
+crbug.com/1113629 compositing/iframes/become-composited-nested-iframes.html [ Failure ]
+crbug.com/1113629 compositing/iframes/become-overlapped-iframe.html [ Failure ]
+crbug.com/1113629 compositing/iframes/composited-parent-iframe.html [ Failure ]
+crbug.com/1113629 compositing/iframes/connect-compositing-iframe-delayed.html [ Failure ]
+crbug.com/1113629 compositing/iframes/connect-compositing-iframe.html [ Failure ]
+crbug.com/1113629 compositing/iframes/connect-compositing-iframe2.html [ Failure ]
+crbug.com/1113629 compositing/iframes/connect-compositing-iframe3.html [ Failure ]
+crbug.com/1113629 compositing/iframes/enter-compositing-iframe.html [ Failure ]
+crbug.com/1113629 compositing/iframes/iframe-resize.html [ Failure ]
+crbug.com/1113629 compositing/iframes/iframe-size-from-zero.html [ Failure ]
+crbug.com/1113629 compositing/iframes/invisible-nested-iframe-show.html [ Failure ]
+crbug.com/1113629 compositing/iframes/overlapped-iframe-iframe.html [ Failure ]
+crbug.com/1113629 compositing/iframes/overlapped-iframe.html [ Failure ]
+crbug.com/1113629 compositing/iframes/overlapped-nested-iframes.html [ Failure ]
+crbug.com/1113629 compositing/iframes/resizer.html [ Failure ]
+crbug.com/1113629 compositing/iframes/scrolling-iframe.html [ Failure ]
+crbug.com/1113629 compositing/rtl/rtl-iframe-absolute-overflow-scrolled.html [ Failure ]
+crbug.com/1113629 compositing/rtl/rtl-iframe-absolute-overflow.html [ Failure ]
+crbug.com/1113629 compositing/rtl/rtl-iframe-absolute.html [ Failure ]
+crbug.com/1113629 compositing/rtl/rtl-iframe-fixed-overflow-scrolled.html [ Failure ]
+crbug.com/1113629 compositing/rtl/rtl-iframe-fixed-overflow.html [ Failure Crash ]
+crbug.com/1113629 compositing/rtl/rtl-iframe-fixed.html [ Failure ]
+crbug.com/1113629 fast/sub-pixel/transformed-iframe-copy-on-scroll.html [ Failure ]
+crbug.com/1113629 paint/invalidation/compositing/overlap-test-with-filter.html [ Failure ]
+crbug.com/1113629 paint/invalidation/scroll/composited-iframe-scroll-repaint.html [ Failure ]
+crbug.com/1113629 paint/invalidation/scroll/repaint-during-scroll-with-zoom.html [ Failure ]
+
 # --- Begin CompositeAfterPaint Tests --
 # Only whitelisted tests run under the virtual suite.
 # More tests run with CompositeAfterPaint on the flag-specific try bot.