Make cc/paint have concrete types

cc/paint/paint_record.h

Index: cc/paint/paint_record.h
diff --git a/cc/paint/paint_record.h b/cc/paint/paint_record.h
index a376394cc84e9e79eefe16a0b04a37abd2c216c7..39820ffd30bc92e1f1986b409394463fdaef5351 100644
--- a/cc/paint/paint_record.h
+++ b/cc/paint/paint_record.h
@@ -5,27 +5,49 @@
 #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;
-
-inline const SkPicture* ToSkPicture(const PaintRecord* record) {
-  return record;
+class PaintCanvas;
+
+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()));
 }
 
-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()));
 }
 
 }  // namespace cc