Traverse into child LayoutViews during invalidateTreeIfNeeded

Source/core/layout/PaintInvalidationState.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/layout/PaintInvalidationState.h"
 
 #include "core/layout/LayoutInline.h"
 #include "core/layout/LayoutView.h"
 #include "core/layout/svg/LayoutSVGModelObject.h"
 #include "core/layout/svg/LayoutSVGRoot.h"
 #include "core/paint/DeprecatedPaintLayer.h"
 
 namespace blink {
 
-PaintInvalidationState::PaintInvalidationState(const LayoutView& layoutView, Vector<LayoutObject*>& pendingDelayedPaintInvalidations)
+PaintInvalidationState::PaintInvalidationState(const LayoutView& layoutView, Vector<LayoutObject*>& pendingDelayedPaintInvalidations, PaintInvalidationState* ownerPaintInvalidationState)
     : m_clipped(false)
     , m_cachedOffsetsEnabled(true)
     , m_forceCheckForPaintInvalidation(false)
     , m_paintInvalidationContainer(*layoutView.containerForPaintInvalidation())
     , m_pendingDelayedPaintInvalidations(pendingDelayedPaintInvalidations)
 {
     bool establishesPaintInvalidationContainer = layoutView == m_paintInvalidationContainer;
     if (!establishesPaintInvalidationContainer) {
-        if (!layoutView.supportsPaintInvalidationStateCachedOffsets()) {
+        if ((ownerPaintInvalidationState && !ownerPaintInvalidationState->m_cachedOffsetsEnabled)
+            || !layoutView.supportsPaintInvalidationStateCachedOffsets()) {
             m_cachedOffsetsEnabled = false;
             return;
         }
+        if (ownerPaintInvalidationState && ownerPaintInvalidationState->m_forceCheckForPaintInvalidation)
+            m_forceCheckForPaintInvalidation = true;
         FloatPoint point = layoutView.localToContainerPoint(FloatPoint(), &m_paintInvalidationContainer, TraverseDocumentBoundaries);
         m_paintOffset = LayoutSize(point.x(), point.y());
     }
     m_clipRect = layoutView.viewRect();
     m_clipRect.move(m_paintOffset);
     m_clipped = true;
 }
 
 PaintInvalidationState::PaintInvalidationState(PaintInvalidationState& next, LayoutBoxModelObject& layoutObject, const LayoutBoxModelObject& paintInvalidationContainer)
     : m_clipped(false)
@@ skipping 88 matching lines @@
     // to be always invalidated in-time.
     if (box.usesCompositedScrolling())
         ASSERT(!m_clipped); // The box should establish paint invalidation container, so no m_clipped inherited.
     else
         addClipRectRelativeToPaintOffset(LayoutSize(box.layer()->size()));
 
     m_paintOffset -= box.scrolledContentOffset();
 }
 
 } // namespace blink