Move scroll event handlers from layer to layer tree view.

cc/layers/layer.h

 // Copyright 2010 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_LAYERS_LAYER_H_
 #define CC_LAYERS_LAYER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 266 matching lines @@
     return user_scrollable_horizontal_;
   }
   bool user_scrollable_vertical() const { return user_scrollable_vertical_; }
 
   void AddMainThreadScrollingReasons(uint32_t main_thread_scrolling_reasons);
   void ClearMainThreadScrollingReasons();
   bool should_scroll_on_main_thread() const {
     return !!main_thread_scrolling_reasons_;
   }
 
-  void SetHaveScrollEventHandlers(bool have_scroll_event_handlers);
-  bool have_scroll_event_handlers() const {
-    return have_scroll_event_handlers_;
-  }
-
   void SetNonFastScrollableRegion(const Region& non_fast_scrollable_region);
   const Region& non_fast_scrollable_region() const {
     return non_fast_scrollable_region_;
   }
 
   void SetTouchEventHandlerRegion(const Region& touch_event_handler_region);
   const Region& touch_event_handler_region() const {
     return touch_event_handler_region_;
   }
 
@@ skipping 411 matching lines @@
   int transform_tree_index_;
   int effect_tree_index_;
   int clip_tree_index_;
   int scroll_tree_index_;
   int property_tree_sequence_number_;
   uint64_t element_id_;
   uint32_t mutable_properties_;
   gfx::Vector2dF offset_to_transform_parent_;
   uint32_t main_thread_scrolling_reasons_;
   bool should_flatten_transform_from_property_tree_ : 1;
-  bool have_scroll_event_handlers_ : 1;
   bool user_scrollable_horizontal_ : 1;
   bool user_scrollable_vertical_ : 1;
   bool is_root_for_isolated_group_ : 1;
   bool is_container_for_fixed_position_layers_ : 1;
   bool is_drawable_ : 1;
   bool draws_content_ : 1;
   bool hide_layer_and_subtree_ : 1;
   bool masks_to_bounds_ : 1;
   bool contents_opaque_ : 1;
   bool double_sided_ : 1;
@@ skipping 49 matching lines @@
 
   std::vector<FrameTimingRequest> frame_timing_requests_;
   bool frame_timing_requests_dirty_;
 
   DISALLOW_COPY_AND_ASSIGN(Layer);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_LAYER_H_