tracing: Make ConvertableToTraceFormat move-only scoped_ptr

cc/debug/layer_debug_info.h

+// Copyright 2016 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_DEBUG_LAYER_DEBUG_INFO_H_
+#define CC_DEBUG_LAYER_DEBUG_INFO_H_
+
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace base {
+namespace trace_event {
+class ConvertableToTraceFormat;
+}
+}
+
+namespace cc {
+
+// A wrapper around ConvertableToTraceFormat which allows shared (refcounted)
+// memory ownership of the Layer's DebugInfo.
+class LayerDebugInfo : public base::RefCounted<LayerDebugInfo> {
+ public:
+  explicit LayerDebugInfo(
+      scoped_ptr<base::trace_event::ConvertableToTraceFormat> raw);
+
+  void AppendAsTraceFormat(std::string* out) const;
+
+ private:
+  friend class base::RefCounted<LayerDebugInfo>;
+  virtual ~LayerDebugInfo();
+
+  scoped_ptr<base::trace_event::ConvertableToTraceFormat> raw_;
+
+  DISALLOW_COPY_AND_ASSIGN(LayerDebugInfo);
+};
+
+}  // namespace cc
+
+#endif  // CC_DEBUG_LAYER_DEBUG_INFO_H_