Implement CSS: scroll-boundary-behavior

cc/layers/layer_impl.h

Index: cc/layers/layer_impl.h
diff --git a/cc/layers/layer_impl.h b/cc/layers/layer_impl.h
index d8010996ec46a58563110a985c8fc02b22c91cfa..c28ab65e6db3d2239a9094fb03b74f9a7d14b3eb 100644
--- a/cc/layers/layer_impl.h
+++ b/cc/layers/layer_impl.h
@@ -22,6 +22,7 @@
 #include "cc/base/synced_property.h"
 #include "cc/cc_export.h"
 #include "cc/input/input_handler.h"
+#include "cc/input/scroll_boundary_behavior.h"
 #include "cc/layers/draw_properties.h"
 #include "cc/layers/layer_collections.h"
 #include "cc/layers/layer_impl_test_properties.h"
@@ -289,6 +290,11 @@ class CC_EXPORT LayerImpl {
   gfx::ScrollOffset ClampScrollOffsetToLimits(gfx::ScrollOffset offset) const;
   gfx::Vector2dF ClampScrollToMaxScrollOffset();
 
+  void SetScrollBoundaryBehavior(ScrollBoundaryBehavior);
+  ScrollBoundaryBehavior scrollBoundaryBehavior() {
+    return scroll_boundary_behavior_;
+  }
+
   // Returns the delta of the scroll that was outside of the bounds of the
   // initial scroll
   gfx::Vector2dF ScrollBy(const gfx::Vector2dF& scroll);
@@ -559,6 +565,8 @@ class CC_EXPORT LayerImpl {
   bool needs_push_properties_ : 1;
   bool scrollbars_hidden_ : 1;
 
+  ScrollBoundaryBehavior scroll_boundary_behavior_;
+
   DISALLOW_COPY_AND_ASSIGN(LayerImpl);
 };