Convert //cc from scoped_ptr to std::unique_ptr.

cc/tiles/picture_layer_tiling.h

Index: cc/tiles/picture_layer_tiling.h
diff --git a/cc/tiles/picture_layer_tiling.h b/cc/tiles/picture_layer_tiling.h
index 816ac8efe5954927ba7c77e9a955b6da3fc327a7..c2be058ff143ecdcd5861627ae1cd1b9f8a18fe5 100644
--- a/cc/tiles/picture_layer_tiling.h
+++ b/cc/tiles/picture_layer_tiling.h
@@ -9,12 +9,12 @@
 #include <stdint.h>
 
 #include <map>
+#include <memory>
 #include <unordered_map>
 #include <utility>
 #include <vector>
 
 #include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
 #include "cc/base/cc_export.h"
 #include "cc/base/region.h"
 #include "cc/base/tiling_data.h"
@@ -88,7 +88,7 @@ class CC_EXPORT PictureLayerTiling {
       float content_to_screen_scale);
 
   // Create a tiling with no tiles. CreateTile() must be called to add some.
-  static scoped_ptr<PictureLayerTiling> Create(
+  static std::unique_ptr<PictureLayerTiling> Create(
       WhichTree tree,
       float contents_scale,
       scoped_refptr<RasterSource> raster_source,