Paint backgrounds of a table section/row in one display item

third_party/WebKit/Source/core/layout/LayoutTableBoxComponent.cpp

Index: third_party/WebKit/Source/core/layout/LayoutTableBoxComponent.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutTableBoxComponent.cpp b/third_party/WebKit/Source/core/layout/LayoutTableBoxComponent.cpp
index 3a4bf18879baaedeb302bda9eb6014d0ed1337bb..9d54c00f2d9a0a7d91ebdbeaa390c237290faed4 100644
--- a/third_party/WebKit/Source/core/layout/LayoutTableBoxComponent.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutTableBoxComponent.cpp
@@ -5,6 +5,7 @@
 #include "core/layout/LayoutTableBoxComponent.h"
 
 #include "core/layout/LayoutTable.h"
+#include "core/paint/ObjectPaintInvalidator.h"
 #include "core/style/ComputedStyle.h"
 
 namespace blink {
@@ -25,4 +26,24 @@ bool LayoutTableBoxComponent::doCellsHaveDirtyWidth(
          !oldStyle.border().sizeEquals(tablePart.style()->border());
 }
 
+void LayoutTableBoxComponent::MutableForPainting::updatePaintResult(
+    PaintResult paintResult,
+    const CullRect& paintRect) {
+  DCHECK_EQ(m_layoutObject.document().lifecycle().state(),
+            DocumentLifecycle::LifecycleState::InPaint);
+
+  // A table row or section may paint large background display item which
+  // contains paint operations of the background in each contained cell.
+  // The display item can be clipped by the paint rect to avoid painting
+  // on areas not interested. If we didn't fully paint and paint rect changes,
+  // we need to invalidate the display item (using setDisplayItemUncached()
+  // because we are already in painting.)
+  auto& box = static_cast<LayoutTableBoxComponent&>(m_layoutObject);
+  if (box.m_lastPaintResult != FullyPainted && box.m_lastPaintRect != paintRect)
+    m_layoutObject.setDisplayItemsUncached();
+
+  box.m_lastPaintResult = paintResult;
+  box.m_lastPaintRect = paintRect;
+}
+
 }  // namespace blink