cc: Do bitmap conversion for RasterBuffer in the worker thread.

cc/resources/raster_buffer.h

Index: cc/resources/raster_buffer.h
diff --git a/cc/resources/raster_buffer.h b/cc/resources/raster_buffer.h
new file mode 100644
index 0000000000000000000000000000000000000000..f1a04ca2a367ae5fb0fbbfbfd260c571211c60ab
--- /dev/null
+++ b/cc/resources/raster_buffer.h
@@ -0,0 +1,23 @@
+// Copyright 2014 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_RESOURCES_RASTER_BUFFER_H_
+#define CC_RESOURCES_RASTER_BUFFER_H_
+
+class SkCanvas;
+
+namespace cc {
+
+class RasterBuffer {
+ public:
+  virtual SkCanvas* AcquireSkCanvas() = 0;
+  virtual void ReleaseSkCanvas() = 0;

[reveman, 2014/08/12 14:31:26]

nit: maybe require the SkCanvas* to be passed to ReleaseSkCanvas() so that an
implementation that is not interested in caching the canvas can just unref it
there instead of keeping an internal ref to it.

[auygun, 2014/08/13 14:18:53]

Acknowledged.

+
+ protected:
+  virtual ~RasterBuffer() {}
+};
+
+}  // namespace cc
+
+#endif  // CC_RESOURCES_RASTER_BUFFER_H_