Add a multi-threaded rendering example.

examples/ui/noodles/frame.h

+// Copyright 2015 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 EXAMPLES_UI_NOODLES_FRAME_H_
+#define EXAMPLES_UI_NOODLES_FRAME_H_
+
+#include "base/macros.h"
+#include "mojo/services/geometry/interfaces/geometry.mojom.h"
+#include "mojo/services/gfx/composition/interfaces/scenes.mojom.h"
+#include "skia/ext/refptr.h"
+
+class SkCanvas;
+class SkPicture;
+
+namespace examples {
+
+// A frame of content to be rasterized.
+// Instances of this object are created by the view's thread and sent to
+// the rasterizer's thread to be drawn.
+class Frame {
+ public:
+  Frame(const mojo::Size& size,
+        skia::RefPtr<SkPicture> picture,
+        mojo::gfx::composition::SceneMetadataPtr scene_metadata);
+  ~Frame();
+
+  const mojo::Size& size() { return size_; }
+
+  mojo::gfx::composition::SceneMetadataPtr TakeSceneMetadata() {
+    return scene_metadata_.Pass();
+  }
+
+  void Paint(SkCanvas* canvas);
+
+ private:
+  mojo::Size size_;
+  skia::RefPtr<SkPicture> picture_;
+  mojo::gfx::composition::SceneMetadataPtr scene_metadata_;
+
+  DISALLOW_COPY_AND_ASSIGN(Frame);
+};
+
+}  // namespace examples
+
+#endif  // EXAMPLES_UI_NOODLES_FRAME_H_