Implement a paint offset cache for slimming paint v2

Source/core/paint/ObjectPainter.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/ObjectPainter.h"
 
 #include "core/layout/LayoutInline.h"
 #include "core/layout/LayoutObject.h"
 #include "core/layout/LayoutTheme.h"
@@ skipping 181 matching lines @@
 
     const ComputedStyle& styleToUse = m_layoutObject.styleRef();
     if (!styleToUse.hasOutline() || styleToUse.visibility() != VISIBLE)
         return;
 
     // Only paint the focus ring by hand if the theme isn't able to draw the focus ring.
     bool paintFocusRing = styleToUse.outlineStyleIsAuto();
     if (paintFocusRing && !LayoutTheme::theme().shouldDrawDefaultFocusRing(&m_layoutObject))
         return;
 
-    if (LayoutObjectDrawingRecorder::useCachedDrawingIfPossible(*paintInfo.context, m_layoutObject, paintInfo.phase))
+    if (LayoutObjectDrawingRecorder::useCachedDrawingIfPossible(*paintInfo.context, m_layoutObject, paintInfo.phase, paintOffset))
         return;
 
     Vector<LayoutRect> outlineRects;
     m_layoutObject.addOutlineRects(outlineRects, paintOffset);
 
     Vector<IntRect> pixelSnappedOutlineRects;
     for (auto& r : outlineRects)
         pixelSnappedOutlineRects.append(pixelSnappedIntRect(r));
 
     IntRect unitedOutlineRect = unionRect(pixelSnappedOutlineRects);
     if (unitedOutlineRect.isEmpty()) {
         if (paintFocusRing)
             return;
         // We need to draw an outline around an empty point.
         IntRect emptyPointRect = pixelSnappedIntRect(LayoutRect(paintOffset, LayoutSize()));
         pixelSnappedOutlineRects.append(emptyPointRect);
         unitedOutlineRect = emptyPointRect;
     }
 
     IntRect bounds = unitedOutlineRect;
     bounds.inflate(m_layoutObject.styleRef().outlineOutsetExtent());
-    LayoutObjectDrawingRecorder recorder(*paintInfo.context, m_layoutObject, paintInfo.phase, bounds);
+    LayoutObjectDrawingRecorder recorder(*paintInfo.context, m_layoutObject, paintInfo.phase, bounds, paintOffset);
 
     Color color = m_layoutObject.resolveColor(styleToUse, CSSPropertyOutlineColor);
     if (styleToUse.outlineStyleIsAuto()) {
         paintInfo.context->drawFocusRing(pixelSnappedOutlineRects, styleToUse.outlineWidth(), styleToUse.outlineOffset(), color);
         return;
     }
 
     if (unitedOutlineRect == pixelSnappedOutlineRects[0]) {
         paintSingleRectangleOutline(paintInfo, unitedOutlineRect, styleToUse, color);
         return;
@@ skipping 23 matching lines @@
     KURL url = toElement(m_layoutObject.node())->hrefURL();
     if (!url.isValid())
         return;
 
     Vector<LayoutRect> outlineRects;
     m_layoutObject.addOutlineRects(outlineRects, paintOffset);
     IntRect rect = pixelSnappedIntRect(unionRect(outlineRects));
     if (rect.isEmpty())
         return;
 
-    if (LayoutObjectDrawingRecorder::useCachedDrawingIfPossible(*paintInfo.context, m_layoutObject, DisplayItem::PrintedContentPDFURLRect))
+    if (LayoutObjectDrawingRecorder::useCachedDrawingIfPossible(*paintInfo.context, m_layoutObject, DisplayItem::PrintedContentPDFURLRect, paintOffset))
         return;
 
-    LayoutObjectDrawingRecorder recorder(*paintInfo.context, m_layoutObject, DisplayItem::PrintedContentPDFURLRect, rect);
+    LayoutObjectDrawingRecorder recorder(*paintInfo.context, m_layoutObject, DisplayItem::PrintedContentPDFURLRect, rect, paintOffset);
     if (url.hasFragmentIdentifier() && equalIgnoringFragmentIdentifier(url, m_layoutObject.document().baseURL())) {
         String fragmentName = url.fragmentIdentifier();
         if (m_layoutObject.document().findAnchor(fragmentName))
             paintInfo.context->setURLFragmentForRect(fragmentName, rect);
         return;
     }
     paintInfo.context->setURLForRect(url, rect);
 }
 
 void ObjectPainter::drawLineForBoxSide(GraphicsContext* graphicsContext, int x1, int y1, int x2, int y2,
@@ skipping 239 matching lines @@
         quad[1] = FloatPoint(x1, y2 - std::max(adjacentWidth2, 0));
         quad[2] = FloatPoint(x2, y2 - std::max(-adjacentWidth2, 0));
         quad[3] = FloatPoint(x2, y1 + std::max(-adjacentWidth1, 0));
         break;
     }
 
     graphicsContext->fillPolygon(4, quad, color, antialias);
 }
 
 } // namespace blink