cc: Don't create SyncedPropety instances on the main thread.

cc/trees/layer_tree_impl.h

 // Copyright 2012 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.
 
 #ifndef CC_TREES_LAYER_TREE_IMPL_H_
 #define CC_TREES_LAYER_TREE_IMPL_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 185 matching lines @@
   void set_background_color(SkColor color) { background_color_ = color; }
 
   bool has_transparent_background() const {
     return has_transparent_background_;
   }
   void set_has_transparent_background(bool transparent) {
     has_transparent_background_ = transparent;
   }
 
   void UpdatePropertyTreeScrollingAndAnimationFromMainThread();
-  void UpdatePropertyTreeScrollOffset(PropertyTrees* property_trees) {
-    property_trees_.scroll_tree.UpdateScrollOffsetMap(
-        &property_trees->scroll_tree.scroll_offset_map(), this);
-  }
   void SetPageScaleOnActiveTree(float active_page_scale);
   void PushPageScaleFromMainThread(float page_scale_factor,
                                    float min_page_scale_factor,
                                    float max_page_scale_factor);
   float current_page_scale_factor() const {
     return page_scale_factor()->Current(IsActiveTree());
   }
   float min_page_scale_factor() const { return min_page_scale_factor_; }
   float max_page_scale_factor() const { return max_page_scale_factor_; }
 
@@ skipping 342 matching lines @@
 
   std::unique_ptr<PendingPageScaleAnimation> pending_page_scale_animation_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(LayerTreeImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_IMPL_H_