[SPv2] Add CSS mix-blend-mode support

third_party/WebKit/Source/core/paint/PaintLayer.cpp

Index: third_party/WebKit/Source/core/paint/PaintLayer.cpp
diff --git a/third_party/WebKit/Source/core/paint/PaintLayer.cpp b/third_party/WebKit/Source/core/paint/PaintLayer.cpp
index 63f32afe660e09352012e34d3fdaf73880a581f8..de0ed6011d1012d7f5f62c2db0e88ad7d791019e 100644
--- a/third_party/WebKit/Source/core/paint/PaintLayer.cpp
+++ b/third_party/WebKit/Source/core/paint/PaintLayer.cpp
@@ -699,6 +699,8 @@ void PaintLayer::updateScrollingStateAfterCompositingChange() {
 
 void PaintLayer::updateDescendantDependentFlags() {
   if (m_needsDescendantDependentFlagsUpdate) {
+    bool oldHasNonIsolatedDescendantWithBlendMode =
+        m_hasNonIsolatedDescendantWithBlendMode;
     m_hasVisibleDescendant = false;
     m_hasNonIsolatedDescendantWithBlendMode = false;
     m_hasDescendantWithClipPath = false;
@@ -727,6 +729,10 @@ void PaintLayer::updateDescendantDependentFlags() {
                                             .rootScrollerPaintLayer());
     }
 
+    if (RuntimeEnabledFeatures::slimmingPaintInvalidationEnabled() &&
+        oldHasNonIsolatedDescendantWithBlendMode !=
+            static_cast<bool>(m_hasNonIsolatedDescendantWithBlendMode))
+      layoutObject()->setNeedsPaintPropertyUpdate();
     m_needsDescendantDependentFlagsUpdate = false;
   }