Enable fast/images with slimming paint

Source/core/paint/LayerClipRecorder.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/paint/LayerClipRecorder.h"
+
 #include "core/paint/ClipRecorder.h"
-
 #include "core/rendering/ClipRect.h"
 #include "core/rendering/RenderLayer.h"
 #include "core/rendering/RenderView.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/geometry/IntRect.h"
 #include "platform/graphics/GraphicsContext.h"
 
 namespace blink {
 
 void ClipDisplayItem::replay(GraphicsContext* context)
 {
     context->save();
     context->clip(m_clipRect);
     for (RoundedRect roundedRect : m_roundedRectClips)
         context->clipRoundedRect(roundedRect);
 }
 
 void EndClipDisplayItem::replay(GraphicsContext* context)
 {
     context->restore();
 }
 
-ClipRecorder::ClipRecorder(const RenderLayerModelObject* renderer, GraphicsContext* graphicsContext, DisplayItem::Type clipType, const ClipRect& clipRect,
+LayerClipRecorder::LayerClipRecorder(const RenderLayerModelObject* renderer, GraphicsContext* graphicsContext, DisplayItem::Type clipType, const ClipRect& clipRect,
     const LayerPaintingInfo* localPaintingInfo, const LayoutPoint& fragmentOffset, PaintLayerFlags paintFlags, BorderRadiusClippingRule rule)
     : m_graphicsContext(graphicsContext)
     , m_renderer(renderer)
 {
     IntRect snappedClipRect = pixelSnappedIntRect(clipRect.rect());
     OwnPtr<ClipDisplayItem> clipDisplayItem = adoptPtr(new ClipDisplayItem(renderer, clipType, snappedClipRect));
     if (localPaintingInfo && clipRect.hasRadius())
         collectRoundedRectClips(*renderer->layer(), *localPaintingInfo, graphicsContext, fragmentOffset, paintFlags, rule, clipDisplayItem->roundedRectClips());
     if (!RuntimeEnabledFeatures::slimmingPaintEnabled()) {
         clipDisplayItem->replay(graphicsContext);
     } else {
         m_renderer->view()->viewDisplayList().add(clipDisplayItem.release());
     }
 }
 
 static bool inContainingBlockChain(RenderLayer* startLayer, RenderLayer* endLayer)
 {
     if (startLayer == endLayer)
         return true;
 
     RenderView* view = startLayer->renderer()->view();
     for (RenderBlock* currentBlock = startLayer->renderer()->containingBlock(); currentBlock && currentBlock != view; currentBlock = currentBlock->containingBlock()) {
         if (currentBlock->layer() == endLayer)
             return true;
     }
 
     return false;
 }
 
-void ClipRecorder::collectRoundedRectClips(RenderLayer& renderLayer, const LayerPaintingInfo& localPaintingInfo, GraphicsContext* context, const LayoutPoint& fragmentOffset, PaintLayerFlags paintFlags,
+void LayerClipRecorder::collectRoundedRectClips(RenderLayer& renderLayer, const LayerPaintingInfo& localPaintingInfo, GraphicsContext* context, const LayoutPoint& fragmentOffset, PaintLayerFlags paintFlags,
     BorderRadiusClippingRule rule, Vector<RoundedRect>& roundedRectClips)
 {
     // If the clip rect has been tainted by a border radius, then we have to walk up our layer chain applying the clips from
     // any layers with overflow. The condition for being able to apply these clips is that the overflow object be in our
     // containing block chain so we check that also.
     for (RenderLayer* layer = rule == IncludeSelfForBorderRadius ? &renderLayer : renderLayer.parent(); layer; layer = layer->parent()) {
         // Composited scrolling layers handle border-radius clip in the compositor via a mask layer. We do not
         // want to apply a border-radius clip to the layer contents itself, because that would require re-rastering
         // every frame to update the clip. We only want to make sure that the mask layer is properly clipped so
         // that it can in turn clip the scrolled contents in the compositor.
         if (layer->needsCompositedScrolling() && !(paintFlags & PaintLayerPaintingChildClippingMaskPhase))
             break;
 
         if (layer->renderer()->hasOverflowClip() && layer->renderer()->style()->hasBorderRadius() && inContainingBlockChain(&renderLayer, layer)) {
             LayoutPoint delta(fragmentOffset);
             layer->convertToLayerCoords(localPaintingInfo.rootLayer, delta);
             roundedRectClips.append(layer->renderer()->style()->getRoundedInnerBorderFor(LayoutRect(delta, LayoutSize(layer->size()))));
         }
 
         if (layer == localPaintingInfo.rootLayer)
             break;
     }
 }
 
-ClipRecorder::~ClipRecorder()
+LayerClipRecorder::~LayerClipRecorder()
 {
     if (RuntimeEnabledFeatures::slimmingPaintEnabled()) {
         OwnPtr<EndClipDisplayItem> endClip = adoptPtr(new EndClipDisplayItem(m_renderer));
         m_renderer->view()->viewDisplayList().add(endClip.release());
     } else {
         m_graphicsContext->restore();
     }
 }
 
 #ifndef NDEBUG
 WTF::String ClipDisplayItem::asDebugString() const
 {
     return String::format("{%s, type: \"%s\", clipRect: [%d,%d,%d,%d]}",
         rendererDebugString(renderer()).utf8().data(), typeAsDebugString(type()).utf8().data(),
         m_clipRect.x(), m_clipRect.y(), m_clipRect.width(), m_clipRect.height());
 }
 #endif
 
 } // namespace blink