[No submit][SPInvalidation] Track paint offset change

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

Index: third_party/WebKit/Source/core/paint/PaintInvalidator.cpp
diff --git a/third_party/WebKit/Source/core/paint/PaintInvalidator.cpp b/third_party/WebKit/Source/core/paint/PaintInvalidator.cpp
index ae82764dc2734a175579fa0bf7c61d7246ea600f..ca95d93dca0c9c8996d139183f7af9ddca39ac3e 100644
--- a/third_party/WebKit/Source/core/paint/PaintInvalidator.cpp
+++ b/third_party/WebKit/Source/core/paint/PaintInvalidator.cpp
@@ -192,6 +192,51 @@ LayoutPoint PaintInvalidator::computeLocationInBacking(
   return LayoutPoint(point);
 }
 
+static LayoutPoint computePaintOffset(const LayoutObject& object,
+                                      PaintInvalidatorContext& context) {
+  LayoutPoint paintOffset = context.treeBuilderContext.current.paintOffset;
+  if (RuntimeEnabledFeatures::slimmingPaintV2Enabled())
+    return paintOffset;
+
+  if (object.isSVG() && !object.isSVGRoot())
+    return paintOffset;
+
+  if (object.isLayoutView() ||
+      (object.hasLayer() &&
+       toLayoutBoxModelObject(object).layer()->paintsWithTransform(
+           GlobalPaintNormalPhase))) {
+    if (object != context.paintInvalidationContainer) {
+      context.shouldAdjustPaintOffsetToContainer = false;
+      LOG(ERROR) << "reset shouldAdjustToContainer by " << object.debugName();
+    }
+    if (object != context.paintInvalidationContainerForStackedContents) {
+      LOG(ERROR) << "reset shouldAdjustToContainerForStackedContents by "
+                 << object.debugName();
+      context.shouldAdjustPaintOffsetToContainerForStackedContents = false;
+    }
+  }
+
+  if (context.shouldAdjustPaintOffsetToContainer) {
+    LOG(ERROR) << object.debugName() << " adjust paint offset to "
+               << context.paintInvalidationContainer->debugName()
+               << " paint offset=" << paintOffset.toString();
+    paintOffset -= toIntSize(
+        roundedIntPoint(context.paintInvalidationContainer->paintProperties()
+                            ->localBorderBoxProperties()
+                            ->paintOffset));
+    LOG(ERROR) << "  after adjustment=" << paintOffset.toString();
+  }
+  if (object != context.paintInvalidationContainer &&
+      context.paintInvalidationContainer->usesCompositedScrolling()) {
+    const LayoutBox* box = toLayoutBox(context.paintInvalidationContainer);
+    if (box->hasOverflowClip())
+      paintOffset += box->scrolledContentOffset();
+    LOG(ERROR) << "  after adjustment for scroll offset="
+               << paintOffset.toString();
+  }
+  return paintOffset;
+}
+
 void PaintInvalidator::updatePaintingLayer(const LayoutObject& object,
                                            PaintInvalidatorContext& context) {
   if (object.hasLayer() &&
@@ -264,9 +309,12 @@ void PaintInvalidator::updateContext(const LayoutObject& object,
 
   if (object.isPaintInvalidationContainer()) {
     context.paintInvalidationContainer = toLayoutBoxModelObject(&object);
-    if (object.styleRef().isStackingContext())
+    context.shouldAdjustPaintOffsetToContainer = true;
+    if (object.styleRef().isStackingContext()) {
       context.paintInvalidationContainerForStackedContents =
           toLayoutBoxModelObject(&object);
+      context.shouldAdjustPaintOffsetToContainerForStackedContents = true;
+    }
   } else if (object.isLayoutView()) {
     // paintInvalidationContainerForStackedContents is only for stacked
     // descendants in its own frame, because it doesn't establish stacking
@@ -275,6 +323,8 @@ void PaintInvalidator::updateContext(const LayoutObject& object,
     // this frame's paintInvalidationContainer.
     context.paintInvalidationContainerForStackedContents =
         context.paintInvalidationContainer;
+    context.shouldAdjustPaintOffsetToContainerForStackedContents =
+        context.shouldAdjustPaintOffsetToContainer;
     if (!RuntimeEnabledFeatures::rootLayerScrollingEnabled())
       undoFrameViewContentClipAndScroll.emplace(
           *toLayoutView(object).frameView(), context);
@@ -289,11 +339,14 @@ void PaintInvalidator::updateContext(const LayoutObject& object,
     // container on which the current object is painted.
     context.paintInvalidationContainer =
         context.paintInvalidationContainerForStackedContents;
+    context.shouldAdjustPaintOffsetToContainer =
+        context.shouldAdjustPaintOffsetToContainerForStackedContents;
     if (context.forcedSubtreeInvalidationFlags &
         PaintInvalidatorContext::
-            ForcedSubtreeFullInvalidationForStackedContents)
+            ForcedSubtreeFullInvalidationForStackedContents) {
       context.forcedSubtreeInvalidationFlags |=
           PaintInvalidatorContext::ForcedSubtreeFullInvalidation;
+    }
   }
 
   if (object == context.paintInvalidationContainer) {
@@ -330,8 +383,10 @@ void PaintInvalidator::updateContext(const LayoutObject& object,
   ObjectPaintInvalidator objectPaintInvalidator(object);
   context.oldVisualRect = object.previousVisualRect();
   context.oldLocation = objectPaintInvalidator.previousLocationInBacking();
+  context.oldPaintOffset = object.previousPaintOffset();
   context.newVisualRect = computeVisualRectInBacking(object, context);
   context.newLocation = computeLocationInBacking(object, context);
+  context.newPaintOffset = computePaintOffset(object, context);
 
   IntSize adjustment = object.scrollAdjustmentForPaintInvalidation(
       *context.paintInvalidationContainer);
@@ -339,6 +394,7 @@ void PaintInvalidator::updateContext(const LayoutObject& object,
   context.newVisualRect.move(adjustment);
 
   object.getMutableForPainting().setPreviousVisualRect(context.newVisualRect);
+  object.getMutableForPainting().setPreviousPaintOffset(context.newPaintOffset);
   objectPaintInvalidator.setPreviousLocationInBacking(context.newLocation);
 }
 
@@ -351,6 +407,8 @@ void PaintInvalidator::invalidatePaintIfNeeded(
   context.paintInvalidationContainer =
       context.paintInvalidationContainerForStackedContents =
           &layoutView->containerForPaintInvalidation();
+  context.shouldAdjustPaintOffsetToContainer =
+      context.shouldAdjustPaintOffsetToContainerForStackedContents = true;
   context.paintingLayer = layoutView->layer();
 
   if (!RuntimeEnabledFeatures::rootLayerScrollingEnabled()) {
@@ -369,18 +427,6 @@ void PaintInvalidator::invalidatePaintIfNeeded(
   layoutView->sendMediaPositionChangeNotifications(visibleRect);
 }
 
-static bool hasPercentageTransform(const ComputedStyle& style) {
-  if (TransformOperation* translate = style.translate()) {
-    if (translate->dependsOnBoxSize())
-      return true;
-  }
-  return style.transform().dependsOnBoxSize() ||
-         (style.transformOriginX() != Length(50, Percent) &&
-          style.transformOriginX().isPercentOrCalc()) ||
-         (style.transformOriginY() != Length(50, Percent) &&
-          style.transformOriginY().isPercentOrCalc());
-}
-
 void PaintInvalidator::invalidatePaintIfNeeded(
     const LayoutObject& object,
     PaintInvalidatorContext& context) {
@@ -430,16 +476,11 @@ void PaintInvalidator::invalidatePaintIfNeeded(
       break;
   }
 
-  if (context.oldLocation != context.newLocation)
-    context.forcedSubtreeInvalidationFlags |=
-        PaintInvalidatorContext::ForcedSubtreeInvalidationChecking;
-
-  // TODO(crbug.com/533277): This is a workaround for the bug. Remove when we
-  // detect paint offset change.
-  if (reason != PaintInvalidationNone &&
-      hasPercentageTransform(object.styleRef()))
+  if (context.oldLocation != context.newLocation ||
+      context.oldPaintOffset != context.newPaintOffset) {
     context.forcedSubtreeInvalidationFlags |=
         PaintInvalidatorContext::ForcedSubtreeInvalidationChecking;
+  }
 
   // TODO(crbug.com/490725): This is a workaround for the bug, to force
   // descendant to update visual rects on clipping change.