Make cc/paint have concrete types

cc/paint/paint_record.h

 // 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.
 
 #ifndef CC_PAINT_PAINT_RECORD_H_
 #define CC_PAINT_PAINT_RECORD_H_
 
+#include "base/compiler_specific.h"
+#include "cc/paint/paint_export.h"
 #include "third_party/skia/include/core/SkPicture.h"
 #include "third_party/skia/include/utils/SkPictureUtils.h"
 
 namespace cc {
 
-using PaintRecord = SkPicture;
+class PaintCanvas;
 
-inline const SkPicture* ToSkPicture(const PaintRecord* record) {
-  return record;
+class CC_PAINT_EXPORT PaintRecord : private SkPicture {
+ public:
+  void playback(PaintCanvas* canvas);
+
+  using SkPicture::playback;
+  using SkPicture::approximateBytesUsed;
+  using SkPicture::approximateOpCount;
+  using SkPicture::cullRect;
+  using SkRefCnt::ref;
+  using SkRefCnt::unref;
+
+ private:
+  friend class PaintRecorder;
+  friend const SkPicture* ToSkPicture(const PaintRecord* record);
+  friend SkPicture* ToSkPicture(PaintRecord* record);
+  friend sk_sp<SkPicture> ToSkPicture(sk_sp<PaintRecord> record);
+  friend sk_sp<const SkPicture> ToSkPicture(sk_sp<const PaintRecord> record);
+};
+
+ALWAYS_INLINE const SkPicture* ToSkPicture(const PaintRecord* record) {
+  return static_cast<const SkPicture*>(record);
 }
 
-inline SkPicture* ToSkPicture(PaintRecord* record) {
-  return record;
+ALWAYS_INLINE SkPicture* ToSkPicture(PaintRecord* record) {
+  return static_cast<SkPicture*>(record);
 }
 
-inline sk_sp<SkPicture> ToSkPicture(sk_sp<PaintRecord> record) {
-  return record;
+ALWAYS_INLINE sk_sp<SkPicture> ToSkPicture(sk_sp<PaintRecord> record) {
+  return sk_sp<SkPicture>(ToSkPicture(record.get()));

[danakj, 2017/03/02 19:44:40]

This adopts the pointer. But |record| will deref it, leading to a refcount
mismatch?

 }
 
-inline sk_sp<const SkPicture> ToSkPicture(sk_sp<const PaintRecord> record) {
-  return record;
+ALWAYS_INLINE sk_sp<const SkPicture> ToSkPicture(
+    sk_sp<const PaintRecord> record) {
+  return sk_sp<const SkPicture>(ToSkPicture(record.get()));

[danakj, 2017/03/02 19:44:40]

same?

 }
 
 }  // namespace cc
 
 #endif  // CC_PAINT_PAINT_RECORD_H_