Skip paint property update and visual rect update if no geometry change

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

 // Copyright 2015 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 "core/paint/PaintPropertyTreeBuilder.h"
 
 #include <memory>
 #include "core/dom/DOMNodeIds.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Settings.h"
 #include "core/layout/LayoutInline.h"
 #include "core/layout/LayoutView.h"
 #include "core/layout/compositing/CompositingReasonFinder.h"
 #include "core/layout/svg/LayoutSVGResourceMasker.h"
 #include "core/layout/svg/LayoutSVGRoot.h"
 #include "core/layout/svg/SVGLayoutSupport.h"
 #include "core/layout/svg/SVGResources.h"
 #include "core/layout/svg/SVGResourcesCache.h"
+#include "core/paint/FindPaintOffsetAndVisualRectNeedingUpdate.h"
 #include "core/paint/FindPropertiesNeedingUpdate.h"
 #include "core/paint/ObjectPaintProperties.h"
 #include "core/paint/PaintLayer.h"
 #include "core/paint/SVGRootPainter.h"
 #include "platform/transforms/TransformationMatrix.h"
 #include "wtf/PtrUtil.h"
 
 namespace blink {
 
 PaintPropertyTreeBuilderContext::PaintPropertyTreeBuilderContext()
@@ skipping 1006 matching lines @@
       DCHECK(parentRow && parentRow->isTableRow());
       context.current.paintOffset.moveBy(
           -toLayoutBox(parentRow)->physicalLocation());
     }
   }
 }
 
 void PaintPropertyTreeBuilder::updateForObjectLocationAndSize(
     const LayoutObject& object,
     PaintPropertyTreeBuilderContext& context) {
+#if DCHECK_IS_ON()
+  FindPaintOffsetNeedingUpdateScope checkScope(object, context);
+#endif
+
   if (object.isBoxModelObject()) {
     updatePaintOffset(toLayoutBoxModelObject(object), context);
     updatePaintOffsetTranslation(toLayoutBoxModelObject(object), context);
   }
 
   if (object.paintOffset() != context.current.paintOffset) {
     // Many paint properties depend on paint offset so we force an update of
     // the entire subtree on paint offset changes.
     context.forceSubtreeUpdate = true;
 
@@ skipping 75 matching lines @@
   updateOverflowClip(object, context);
   updatePerspective(object, context);
   updateSvgLocalToBorderBoxTransform(object, context);
   updateScrollAndScrollTranslation(object, context);
   updateOutOfFlowContext(object, context);
 
   context.forceSubtreeUpdate |= object.subtreeNeedsPaintPropertyUpdate();
 }
 
 }  // namespace blink