Optimize offscreen animation: don't update paint properties/visual rects

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc.
  *               All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 1735 matching lines @@
   return ForegroundIsKnownToBeOpaqueInRect(background_rect,
                                            kBackgroundObscurationTestMaxDepth);
 }
 
 void LayoutBox::PaintMask(const PaintInfo& paint_info,
                           const LayoutPoint& paint_offset) const {
   BoxPainter(*this).PaintMask(paint_info, paint_offset);
 }
 
 void LayoutBox::ImageChanged(WrappedImagePtr image, const IntRect*) {
-  // TODO(chrishtr): support PaintInvalidationDelayedFull for animated border
+  // TODO(chrishtr): support kPaintInvalidationDelayedFull for animated border
   // images.
   if ((StyleRef().BorderImage().GetImage() &&
        StyleRef().BorderImage().GetImage()->Data() == image) ||
       (StyleRef().MaskBoxImage().GetImage() &&
        StyleRef().MaskBoxImage().GetImage()->Data() == image) ||
       (StyleRef().BoxReflect() && StyleRef().BoxReflect()->Mask().GetImage() &&
        StyleRef().BoxReflect()->Mask().GetImage()->Data() == image)) {
     SetShouldDoFullPaintInvalidationWithoutGeometryChange();
   } else {
     for (const FillLayer* layer = &StyleRef().MaskLayers(); layer;
@@ skipping 101 matching lines @@
       !BackgroundIsKnownToBeObscured()) {
     SetShouldDoFullPaintInvalidationWithoutGeometryChange(
         kPaintInvalidationDelayedFull);
   }
 
   if (FullPaintInvalidationReason() != kPaintInvalidationDelayedFull ||
       !IntersectsVisibleViewport())
     return;
 
   // Do regular full paint invalidation if the object with
-  // PaintInvalidationDelayedFull is onscreen.
-  if (IntersectsVisibleViewport()) {
-    // Conservatively assume the delayed paint invalidation was caused by
-    // background image change.
-    SetBackgroundChangedSinceLastPaintInvalidation();
-    SetShouldDoFullPaintInvalidationWithoutGeometryChange(
-        kPaintInvalidationFull);
-  }
+  // kPaintInvalidationDelayedFull is onscreen.
+  // Conservatively assume the delayed paint invalidation was caused by
+  // background image change.
+  SetBackgroundChangedSinceLastPaintInvalidation();
+  SetShouldDoFullPaintInvalidationWithoutGeometryChange(kPaintInvalidationFull);
 }
 
 PaintInvalidationReason LayoutBox::InvalidatePaintIfNeeded(
     const PaintInvalidationState& paint_invalidation_state) {
   if (HasBoxDecorationBackground()
       // We also paint overflow controls in background phase.
       || (HasOverflowClip() && GetScrollableArea()->HasOverflowControls())) {
     PaintLayer& layer = paint_invalidation_state.PaintingLayer();
     if (&layer.GetLayoutObject() != this)
       layer.SetNeedsPaintPhaseDescendantBlockBackgrounds();
@@ skipping 4004 matching lines @@
 void LayoutBox::MutableForPainting::
     SavePreviousContentBoxSizeAndLayoutOverflowRect() {
   auto& rare_data = GetLayoutBox().EnsureRareData();
   rare_data.has_previous_content_box_size_and_layout_overflow_rect_ = true;
   rare_data.previous_content_box_size_ = GetLayoutBox().ContentBoxRect().Size();
   rare_data.previous_layout_overflow_rect_ =
       GetLayoutBox().LayoutOverflowRect();
 }
 
 }  // namespace blink