Back PaintRecord with PaintOpBuffer instead of SkPicture

cc/paint/paint_recorder.cc

 // Copyright 2017 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 "cc/paint/paint_recorder.h"
 
+#include "cc/paint/paint_op_buffer.h"
+
 namespace cc {
 
 PaintRecorder::PaintRecorder() = default;
+
 PaintRecorder::~PaintRecorder() = default;
 
+PaintCanvas* PaintRecorder::beginRecording(const SkRect& bounds) {
+  buffer_.reset(new PaintOpBuffer(bounds));
+  canvas_.emplace(buffer_.get(), bounds);
+  return getRecordingCanvas();
+}
+
+sk_sp<PaintRecord> PaintRecorder::finishRecordingAsPicture() {
+  // Some users (e.g. printing) use the existence of the recording canvas
+  // to know if recording is finished, so reset it here.
+  canvas_.reset();
+  // TODO(enne): consider making a mini picture here.

[vmpstr, 2017/03/28 18:27:15]

Do we still need this with the optimization in the paintbuffer?

[enne (OOO), 2017/03/28 19:28:05]

Yeah, it's possible.  I think I would consider making a SmallDrawingDisplayItem
and just copy the memory in there when needed.  This is sort of up in the air
with wanting to merge DisplayItemList and PaintOpBuffer.  If we do that, then no
need for mini pictures anywhere.

+  return std::move(buffer_);
+}
+
 }  // namespace cc