Shifting layer position for sticky element to avoid passing unnessary variable to cc

cc/trees/property_tree_builder.cc

 // Copyright 2014 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/trees/property_tree_builder.h"
 
 #include <stddef.h>
 
 #include <map>
 #include <set>
@@ skipping 58 matching lines @@
 
 static LayerStickyPositionConstraint StickyPositionConstraint(Layer* layer) {
   return layer->sticky_position_constraint();
 }
 
 static LayerStickyPositionConstraint StickyPositionConstraint(
     LayerImpl* layer) {
   return layer->test_properties()->sticky_position_constraint;
 }
 
-static gfx::Size OffsetForStickyPositionFromMainThread(Layer* layer) {
-  return layer->offset_for_sticky_position_from_main_thread();
-}
-
-static gfx::Size OffsetForStickyPositionFromMainThread(LayerImpl* layer) {
-  return layer->test_properties()->offset_for_sticky_position_from_main_thread;
-}
-
 static LayerImplList& Children(LayerImpl* layer) {
   return layer->test_properties()->children;
 }
 
 static const LayerList& Children(Layer* layer) {
   return layer->children();
 }
 
 static LayerImpl* ChildAt(LayerImpl* layer, int index) {
   return layer->test_properties()->children[index];
@@ skipping 466 matching lines @@
     int shifting_containing_block_layer_id =
         sticky_data->constraints.nearest_layer_shifting_containing_block;
     if (shifting_containing_block_layer_id != Layer::INVALID_ID) {
       sticky_data->nearest_node_shifting_containing_block =
           data_for_children->property_trees->transform_tree
               .FindNodeIndexFromOwningLayerId(
                   shifting_containing_block_layer_id);
       DCHECK(sticky_data->nearest_node_shifting_containing_block !=
              TransformTree::kInvalidNodeId);
     }
-    node->offset_for_sticky_position_from_main_thread =
-        gfx::Vector2dF(OffsetForStickyPositionFromMainThread(layer).width(),
-                       OffsetForStickyPositionFromMainThread(layer).height());
   }
 
   node->needs_local_transform_update = true;
   data_from_ancestor.property_trees->transform_tree.UpdateTransforms(node->id);
 
   layer->set_offset_to_transform_parent(gfx::Vector2dF());
 
   // Flattening (if needed) will be handled by |node|.
   layer->set_should_flatten_transform_from_property_tree(false);
 
@@ skipping 819 matching lines @@
       root_layer, page_scale_layer, inner_viewport_scroll_layer,
       outer_viewport_scroll_layer, overscroll_elasticity_layer,
       elastic_overscroll, page_scale_factor, device_scale_factor, viewport,
       device_transform, property_trees, color);
   property_trees->effect_tree.CreateOrReuseRenderSurfaces(
       &render_surfaces, root_layer->layer_tree_impl());
   property_trees->ResetCachedData();
 }
 
 }  // namespace cc