Make cc/paint have concrete types

cc/paint/paint_recorder.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_RECORDER_H_
 #define CC_PAINT_PAINT_RECORDER_H_
 
+#include "base/compiler_specific.h"
+#include "base/memory/ptr_util.h"
+#include "cc/paint/paint_canvas.h"
+#include "cc/paint/paint_record.h"
 #include "third_party/skia/include/core/SkPictureRecorder.h"
 
 namespace cc {
-using PaintRecorder = SkPictureRecorder;
-}
+
+class PaintRecorder : private SkPictureRecorder {

[vmpstr, 2017/03/02 21:52:42]

I'm a bit hesitant about private inheritance... Why this instead of composition?

[enne (OOO), 2017/03/02 23:59:44]

Sure, changed to composition here.  I think PaintRecord needs to stay being
private inheritance so that it's possible to cast directly from sk_sp of
SkPicture to PaintRecord.

+ public:
+  using SkPictureRecorder::SkPictureRecorder;
+  using SkPictureRecorder::RecordFlags;
+  using SkPictureRecorder::FinishFlags;
+
+  ALWAYS_INLINE PaintCanvas* beginRecording(const SkRect& bounds,
+                                            SkBBHFactory* bbhFactory = nullptr,
+                                            uint32_t recordFlags = 0) {
+    canvas_.SetInternalSkCanvas(
+        SkPictureRecorder::beginRecording(bounds, bbhFactory, recordFlags));
+    return getRecordingCanvas();
+  }
+
+  ALWAYS_INLINE PaintCanvas* beginRecording(SkScalar width,
+                                            SkScalar height,
+                                            SkBBHFactory* bbhFactory = nullptr,
+                                            uint32_t recordFlags = 0) {
+    canvas_.SetInternalSkCanvas(SkPictureRecorder::beginRecording(
+        width, height, bbhFactory, recordFlags));
+    return getRecordingCanvas();
+  }
+
+  ALWAYS_INLINE PaintCanvas* getRecordingCanvas() { return &canvas_; }
+
+  ALWAYS_INLINE sk_sp<PaintRecord> finishRecordingAsPicture(
+      uint32_t endFlags = 0) {
+    sk_sp<SkPicture> p = SkPictureRecorder::finishRecordingAsPicture(endFlags);

[vmpstr, 2017/03/02 21:52:42]

p = picture?

+    return sk_ref_sp(static_cast<PaintRecord*>(p.get()));

[vmpstr, 2017/03/02 21:52:42]

That's kind of an awkward pattern... Does static_cast<sk_sp<PaintRecord>>(p) not
work? I think that works for unique_ptr, but I'm guessing sk_sp doesn't
implement this type of conversion

[enne (OOO), 2017/03/02 23:59:44]

Yeah, it doesn't work, sorry.

+  }
+
+  ALWAYS_INLINE sk_sp<PaintRecord> finishRecordingAsPictureWithCull(
+      const SkRect& cullRect,
+      uint32_t endFlags = 0) {
+    sk_sp<SkPicture> p =
+        SkPictureRecorder::finishRecordingAsPictureWithCull(cullRect, endFlags);
+    return sk_ref_sp(static_cast<PaintRecord*>(p.get()));
+  }
+
+ private:
+  PaintCanvas canvas_;
+};
+
+}  // namespace cc
 
 #endif  // CC_PAINT_PAINT_RECORDER_H_