Snap layers in views to physical pixel

ui/compositor/dip_util.h

Index: ui/compositor/dip_util.h
diff --git a/ui/compositor/dip_util.h b/ui/compositor/dip_util.h
index e8d0367ee5436ece07183c36be9269d5c02fece5..cac368170b1ebdb0136caa693b79014793860e4e 100644
--- a/ui/compositor/dip_util.h
+++ b/ui/compositor/dip_util.h
@@ -44,6 +44,13 @@ COMPOSITOR_EXPORT gfx::Rect ConvertRectToPixel(
     const Layer* layer,
     const gfx::Rect& rect_in_dip);
 
+// Snaps the |layer_to_snap| to the physical pixel boundary.
+// |snapped_layer| is a reference layer that should also be
+// snapped at the pysical pixel boundary.
+COMPOSITOR_EXPORT void SnapLayerToPhysicalPixelBoundary(
+    ui::Layer* snapped_layer,
+    ui::Layer* layer_to_snap);
+
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_DIP_UTIL_H_