Use DrawingRecorder::canUseCachedDrawing

Source/core/paint/ImagePainter.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/ImagePainter.h"
 
 #include "core/dom/Document.h"
 #include "core/dom/Element.h"
 #include "core/editing/FrameSelection.h"
@@ skipping 46 matching lines @@
 
     RenderStyle* areaElementStyle = areaElement.computedStyle();
     unsigned short outlineWidth = areaElementStyle->outlineWidth();
     if (!outlineWidth)
         return;
 
     // FIXME: Clip path instead of context when Skia pathops is ready.
     // https://crbug.com/251206
     GraphicsContextStateSaver savedContext(*paintInfo.context);
     IntRect focusRect = m_renderImage.absoluteContentBox();
-    RenderDrawingRecorder recorder(paintInfo.context, &m_renderImage, paintInfo.phase, focusRect);
+    RenderDrawingRecorder recorder(paintInfo.context, m_renderImage, paintInfo.phase, focusRect);
+    if (recorder.canUseCachedDrawing())
+        return;
+
     paintInfo.context->clip(focusRect);
     paintInfo.context->drawFocusRing(path, outlineWidth,
         areaElementStyle->outlineOffset(),
         m_renderImage.resolveColor(areaElementStyle, CSSPropertyOutlineColor));
 }
 
 void ImagePainter::paintReplaced(const PaintInfo& paintInfo, const LayoutPoint& paintOffset)
 {
     LayoutUnit cWidth = m_renderImage.contentWidth();
     LayoutUnit cHeight = m_renderImage.contentHeight();
 
     GraphicsContext* context = paintInfo.context;
 
     if (!m_renderImage.imageResource()->hasImage()) {
         if (paintInfo.phase == PaintPhaseSelection)
             return;
 
         if (cWidth > 2 && cHeight > 2) {
             // Draw an outline rect where the image should be.
             IntRect paintRect = pixelSnappedIntRect(LayoutRect(paintOffset.x() + m_renderImage.borderLeft() + m_renderImage.paddingLeft(), paintOffset.y() + m_renderImage.borderTop() + m_renderImage.paddingTop(), cWidth, cHeight));
-            RenderDrawingRecorder recorder(context, &m_renderImage, paintInfo.phase, paintRect);
+            RenderDrawingRecorder recorder(context, m_renderImage, paintInfo.phase, paintRect);
+            if (recorder.canUseCachedDrawing())
+                return;
+
             context->setStrokeStyle(SolidStroke);
             context->setStrokeColor(Color::lightGray);
             context->setFillColor(Color::transparent);
             context->drawRect(paintRect);
         }
-    } else if (cWidth > 0 && cHeight > 0) {

[chrishtr, 2014/12/12 00:18:08]

Why the change to get rid of the else clause?

[Xianzhu, 2014/12/12 00:56:49]

Restored.

+        return;
+    }
+
+    if (cWidth > 0 && cHeight > 0) {
         LayoutRect contentRect = m_renderImage.contentBoxRect();
         contentRect.moveBy(paintOffset);
         LayoutRect paintRect = m_renderImage.replacedContentRect();
         paintRect.moveBy(paintOffset);
-        RenderDrawingRecorder recorder(context, &m_renderImage, paintInfo.phase, contentRect);
+        RenderDrawingRecorder recorder(context, m_renderImage, paintInfo.phase, contentRect);
+        if (recorder.canUseCachedDrawing())
+            return;
+
         bool clip = !contentRect.contains(paintRect);
         if (clip) {
             context->save();
             context->clip(contentRect);
         }
 
         paintIntoRect(context, paintRect);
 
         if (clip)
             context->restore();
@@ skipping 22 matching lines @@
 
     InterpolationQuality previousInterpolationQuality = context->imageInterpolationQuality();
     context->setImageInterpolationQuality(interpolationQuality);
     context->drawImage(image.get(), alignedRect, CompositeSourceOver, m_renderImage.shouldRespectImageOrientation());
     context->setImageInterpolationQuality(previousInterpolationQuality);
 
     InspectorInstrumentation::didPaintImage(&m_renderImage);
 }
 
 } // namespace blink