Compute and include the offset of the sticky box to its enclosing composited layer.

cc/layers/layer_sticky_position_constraint.cc

 // Copyright 2013 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.
 
 #include "cc/layers/layer_sticky_position_constraint.h"
 #include "cc/proto/gfx_conversions.h"
 #include "cc/proto/layer_sticky_position_constraint.pb.h"
 
 namespace cc {
 
@@ skipping 12 matching lines @@
     const LayerStickyPositionConstraint& other)
     : is_sticky(other.is_sticky),
       is_anchored_left(other.is_anchored_left),
       is_anchored_right(other.is_anchored_right),
       is_anchored_top(other.is_anchored_top),
       is_anchored_bottom(other.is_anchored_bottom),
       left_offset(other.left_offset),
       right_offset(other.right_offset),
       top_offset(other.top_offset),
       bottom_offset(other.bottom_offset),
+      parent_relative_sticky_box_offset(
+          other.parent_relative_sticky_box_offset),
       scroll_container_relative_sticky_box_rect(
           other.scroll_container_relative_sticky_box_rect),
       scroll_container_relative_containing_block_rect(
           other.scroll_container_relative_containing_block_rect) {}
 
 void LayerStickyPositionConstraint::ToProtobuf(
     proto::LayerStickyPositionConstraint* proto) const {
   proto->set_is_sticky(is_sticky);
   proto->set_is_anchored_left(is_anchored_left);
   proto->set_is_anchored_right(is_anchored_right);
   proto->set_is_anchored_top(is_anchored_top);
   proto->set_is_anchored_bottom(is_anchored_bottom);
   proto->set_left_offset(left_offset);
   proto->set_right_offset(right_offset);
   proto->set_top_offset(top_offset);
   proto->set_bottom_offset(bottom_offset);
+  PointToProto(parent_relative_sticky_box_offset,
+               proto->mutable_parent_relative_sticky_box_offset());
   RectToProto(scroll_container_relative_sticky_box_rect,
               proto->mutable_scroll_container_relative_sticky_box_rect());
   RectToProto(scroll_container_relative_containing_block_rect,
               proto->mutable_scroll_container_relative_containing_block_rect());
 }
 
 void LayerStickyPositionConstraint::FromProtobuf(
     const proto::LayerStickyPositionConstraint& proto) {
   is_sticky = proto.is_sticky();
   is_anchored_left = proto.is_anchored_left();
   is_anchored_right = proto.is_anchored_right();
   is_anchored_top = proto.is_anchored_top();
   is_anchored_bottom = proto.is_anchored_bottom();
   left_offset = proto.left_offset();
   right_offset = proto.right_offset();
   top_offset = proto.top_offset();
   bottom_offset = proto.bottom_offset();
+  parent_relative_sticky_box_offset =
+      ProtoToPoint(proto.parent_relative_sticky_box_offset());
   scroll_container_relative_sticky_box_rect =
       ProtoToRect(proto.scroll_container_relative_sticky_box_rect());
   scroll_container_relative_containing_block_rect =
       ProtoToRect(proto.scroll_container_relative_containing_block_rect());
 }
 
 bool LayerStickyPositionConstraint::operator==(
     const LayerStickyPositionConstraint& other) const {
   if (!is_sticky && !other.is_sticky)
     return true;
   return is_sticky == other.is_sticky &&
          is_anchored_left == other.is_anchored_left &&
          is_anchored_right == other.is_anchored_right &&
          is_anchored_top == other.is_anchored_top &&
          is_anchored_bottom == other.is_anchored_bottom &&
          left_offset == other.left_offset &&
          right_offset == other.right_offset && top_offset == other.top_offset &&
          bottom_offset == other.bottom_offset &&
+         parent_relative_sticky_box_offset ==
+             other.parent_relative_sticky_box_offset &&
          scroll_container_relative_sticky_box_rect ==
              other.scroll_container_relative_sticky_box_rect &&
          scroll_container_relative_containing_block_rect ==
              other.scroll_container_relative_containing_block_rect;
 }
 
 bool LayerStickyPositionConstraint::operator!=(
     const LayerStickyPositionConstraint& other) const {
   return !(*this == other);
 }
 
 }  // namespace cc