Raster PictureLayerTiling with fractional translation

cc/layers/picture_layer_impl.h

Index: cc/layers/picture_layer_impl.h
diff --git a/cc/layers/picture_layer_impl.h b/cc/layers/picture_layer_impl.h
index f6a65242bf87195c61f8e5eac4ebc00f4b337abd..07de9ebd11449f55b00efa06c41be82a1e78afec 100644
--- a/cc/layers/picture_layer_impl.h
+++ b/cc/layers/picture_layer_impl.h
@@ -98,11 +98,13 @@ class CC_EXPORT PictureLayerImpl
 
  protected:
   PictureLayerImpl(LayerTreeImpl* tree_impl, int id, bool is_mask);
-  PictureLayerTiling* AddTiling(float contents_scale);
+  PictureLayerTiling* AddTiling(float contents_scale,
+                                const gfx::Vector2dF& contents_translation);
   void RemoveAllTilings();
   void AddTilingsForRasterScale();
   void AddLowResolutionTilingIfNeeded();
   bool ShouldAdjustRasterScale() const;
+  gfx::Vector2dF CalculateRasterTranslation();
   void RecalculateRasterScales();
   void CleanUpTilingsOnActiveLayer(
       const std::vector<PictureLayerTiling*>& used_tilings);