Decouple Canvas from DisplayList and map Picture and PictureRecorder more directly to their Skia co…

sky/engine/core/painting/PictureRecorder.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 "sky/engine/config.h"
 #include "sky/engine/core/painting/PictureRecorder.h"
 
 #include "sky/engine/core/painting/Picture.h"
 
 namespace blink {
 
-PassRefPtr<PictureRecorder> PictureRecorder::create(double width, double height)
-{
-    return adoptRef(new PictureRecorder(FloatSize(width, height)));
-}
-
-PictureRecorder::PictureRecorder(const FloatSize& size)
-    : Canvas(size)
+PictureRecorder::PictureRecorder()
+    : m_pictureRecorder(adoptPtr(new SkPictureRecorder()))
 {
 }
 
 PictureRecorder::~PictureRecorder()
 {
 }
 
+PassRefPtr<Canvas> PictureRecorder::beginRecording(double width, double height)
+{
+    m_canvas = Canvas::create(
+        m_pictureRecorder->beginRecording(width, height));
+    return m_canvas;
+}
+
 PassRefPtr<Picture> PictureRecorder::endRecording()
 {
     if (!isRecording())
         return nullptr;
-    return Picture::create(finishRecording());
+    auto picture = Picture::create(
+        adoptRef(m_pictureRecorder->endRecording()));
+    m_canvas->clearSkCanvas();
+    m_canvas = nullptr;
+    return picture;
 }
 
 } // namespace blink