Invalidate objects when containing block changed

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

Index: third_party/WebKit/Source/core/layout/LayoutBlock.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutBlock.cpp b/third_party/WebKit/Source/core/layout/LayoutBlock.cpp
index 462984483509a30b784e159ba56b086543d82d69..df89bfa0970d97f3c0b8b5af3c6155f08880ae71 100644
--- a/third_party/WebKit/Source/core/layout/LayoutBlock.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutBlock.cpp
@@ -229,21 +229,27 @@ void LayoutBlock::styleWillChange(StyleDifference diff, const ComputedStyle& new
 
     setReplaced(newStyle.isDisplayInlineType());
 
-    if (oldStyle && parent()) {
+    if (oldStyle && parent() && !isLayoutView()) {

[chrishtr, 2015/10/30 18:28:18]

Why this change?

[Xianzhu, 2015/10/30 19:15:28]

Added this because I thought layout view never changes its relationship with its
contained positioned objects because of its style change. The check seems
unnecessary because LayoutView never changes position or transformed related
properties.

Reverted.

         bool oldHasTransformRelatedProperty = oldStyle->hasTransformRelatedProperty();
         bool newHasTransformRelatedProperty = newStyle.hasTransformRelatedProperty();
         bool oldStyleIsContainer = oldStyle->position() != StaticPosition || oldHasTransformRelatedProperty;
 
         if (oldStyleIsContainer && (newStyle.position() == StaticPosition || (oldHasTransformRelatedProperty && !newHasTransformRelatedProperty))) {
-            // Clear our positioned objects list. Our absolutely positioned descendants will be
+            // Clear our positioned objects list. Our absolute and fixed positioned descendants will be
             // inserted into our containing block's positioned objects list during layout.
-            removePositionedObjects(0, NewContainingBlock);
+            removePositionedObjects(nullptr, NewContainingBlock);
         } else if (!oldStyleIsContainer && (newStyle.position() != StaticPosition || newHasTransformRelatedProperty)) {
             // Remove our absolutely positioned descendants from their current containing block.
             // They will be inserted into our positioned objects list during layout.
             if (LayoutBlock* cb = containingBlockForAbsolutePosition())
                 cb->removePositionedObjects(this, NewContainingBlock);
         }
+        if (!oldHasTransformRelatedProperty && newHasTransformRelatedProperty) {
+            // Remove our fixed positioned descendants from their current containing block.
+            // They will be inserted into our positioned objects list during layout.
+            if (LayoutBlock* cb = containerForFixedPosition())
+                cb->removePositionedObjects(this, NewContainingBlock);
+        }
     }
 
     LayoutBox::styleWillChange(diff, newStyle);
@@ -281,7 +287,7 @@ void LayoutBlock::styleDidChange(StyleDifference diff, const ComputedStyle* oldS
 
     if (oldStyle && parent()) {
         if (oldStyle->position() != newStyle.position() && newStyle.position() != StaticPosition) {
-            // Remove our absolutely positioned descendants from their new containing block,
+            // Remove our absolute and fixed positioned descendants from their new containing block,
             // in case containingBlock() changes by the change to the position property.
             // See styleWillChange() for other cases.
             if (LayoutBlock* cb = containingBlock())
@@ -1466,11 +1472,20 @@ void LayoutBlock::removePositionedObjects(LayoutBlock* o, ContainingBlockState c
 
     Vector<LayoutBox*, 16> deadObjects;
     for (auto* positionedObject : *positionedDescendants) {
-        if (!o || positionedObject->isDescendantOf(o)) {
+        if (!o || (positionedObject->isDescendantOf(o) && o != positionedObject)) {
             if (containingBlockState == NewContainingBlock) {
                 positionedObject->setChildNeedsLayout(MarkOnlyThis);
                 if (positionedObject->needsPreferredWidthsRecalculation())
                     positionedObject->setPreferredLogicalWidthsDirty(MarkOnlyThis);
+
+                // The positioned object changing containing block may change paint invalidation container.
+                // Invalidate it (including non-compositing descendants) on its original paint invalidation container.
+                if (!RuntimeEnabledFeatures::slimmingPaintV2Enabled()) {
+                    // This valid because we need to invalidate based on the current status.
+                    DisableCompositingQueryAsserts compositingDisabler;
+                    if (!positionedObject->isPaintInvalidationContainer())
+                        positionedObject->invalidatePaintIncludingNonCompositingDescendants();
+                }
             }
 
             // It is parent blocks job to add positioned child to positioned objects list of its containing block