Update containing block's positioned descendants list when an object becomes out-of-flow-positioned

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 d5bee361778483630ea2d398bcafcbfda68e6899..5f48abd550b1e876e2c7412adcd951bcd14bd824 100644
--- a/third_party/WebKit/Source/core/layout/LayoutBlock.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutBlock.cpp
@@ -223,6 +223,13 @@ void LayoutBlock::styleDidChange(StyleDifference diff, const ComputedStyle* oldS
             // See styleWillChange() for other cases.
             if (LayoutBlock* cb = containingBlock())
                 cb->removePositionedObjects(this, NewContainingBlock);
+                if (isOutOfFlowPositioned()) {
+                    // Insert this object into containing block's positioned descendants list
+                    // in case the parent won't layout. This is needed especially there are
+                    // descendants scheduled for overflow recalc.
+                    cb->insertPositionedObject(this);
+                }
+            }
         }
     }