Move scroll event handlers from layer to layer tree view.

cc/layers/layer_impl.cc

 // 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.
 
 #include "cc/layers/layer_impl.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <utility>
@@ skipping 42 matching lines @@
       scroll_parent_(nullptr),
       clip_parent_(nullptr),
       mask_layer_id_(-1),
       replica_layer_id_(-1),
       layer_id_(id),
       layer_tree_impl_(tree_impl),
       scroll_offset_(scroll_offset),
       scroll_clip_layer_id_(Layer::INVALID_ID),
       main_thread_scrolling_reasons_(
           MainThreadScrollingReason::kNotScrollingOnMain),
-      have_scroll_event_handlers_(false),
       user_scrollable_horizontal_(true),
       user_scrollable_vertical_(true),
       stacking_order_changed_(false),
       double_sided_(true),
       should_flatten_transform_(true),
       should_flatten_transform_from_property_tree_(false),
       layer_property_changed_(false),
       masks_to_bounds_(false),
       contents_opaque_(false),
       is_root_for_isolated_group_(false),
@@ skipping 533 matching lines @@
   // TODO(weiliangc): Should be safely removed after impl side is able to
   // update render surfaces without rebuilding property trees.
   if (layer->has_render_surface() != has_render_surface())
     layer->layer_tree_impl()->set_needs_update_draw_properties();
   layer->SetHasRenderSurface(!!render_surface());
   layer->SetForceRenderSurface(force_render_surface_);
   layer->SetFilters(filters());
   layer->SetBackgroundFilters(background_filters());
   layer->SetMasksToBounds(masks_to_bounds_);
   layer->set_main_thread_scrolling_reasons(main_thread_scrolling_reasons_);
-  layer->SetHaveScrollEventHandlers(have_scroll_event_handlers_);
   layer->SetNonFastScrollableRegion(non_fast_scrollable_region_);
   layer->SetTouchEventHandlerRegion(touch_event_handler_region_);
   layer->SetContentsOpaque(contents_opaque_);
   layer->SetOpacity(opacity_);
   layer->SetBlendMode(blend_mode_);
   layer->SetIsRootForIsolatedGroup(is_root_for_isolated_group_);
   layer->SetPosition(position_);
   layer->SetIsContainerForFixedPositionLayers(
       is_container_for_fixed_position_layers_);
   layer->SetPositionConstraint(position_constraint_);
@@ skipping 128 matching lines @@
   result->Set("DrawTransform", list);
 
   result->SetBoolean("DrawsContent", draws_content_);
   result->SetBoolean("Is3dSorted", Is3dSorted());
   result->SetDouble("OPACITY", opacity());
   result->SetBoolean("ContentsOpaque", contents_opaque_);
 
   if (scrollable())
     result->SetBoolean("Scrollable", true);
 
-  if (have_scroll_event_handlers_)
-    result->SetBoolean("ScrollHandler", have_scroll_event_handlers_);
   if (!touch_event_handler_region_.IsEmpty()) {
     scoped_ptr<base::Value> region = touch_event_handler_region_.AsValue();
     result->Set("TouchRegion", region.release());
   }
 
   list = new base::ListValue;
   for (size_t i = 0; i < children_.size(); ++i)
     list->Append(children_[i]->LayerTreeAsJson());
   result->Set("Children", list);
 
@@ skipping 941 matching lines @@
   bool clipped;
   gfx::QuadF layer_quad =
       MathUtil::MapQuad(ScreenSpaceTransform(),
                         gfx::QuadF(gfx::RectF(gfx::Rect(bounds()))), &clipped);
   MathUtil::AddToTracedValue("layer_quad", layer_quad, state);
   if (!touch_event_handler_region_.IsEmpty()) {
     state->BeginArray("touch_event_handler_region");
     touch_event_handler_region_.AsValueInto(state);
     state->EndArray();
   }
-  if (have_scroll_event_handlers_) {
-    gfx::Rect scroll_rect(bounds());
-    Region scroll_region(scroll_rect);
-    state->BeginArray("scroll_event_handler_region");
-    scroll_region.AsValueInto(state);
-    state->EndArray();
-  }
   if (!non_fast_scrollable_region_.IsEmpty()) {
     state->BeginArray("non_fast_scrollable_region");
     non_fast_scrollable_region_.AsValueInto(state);
     state->EndArray();
   }
   state->BeginArray("children");
   for (size_t i = 0; i < children_.size(); ++i) {
     state->BeginDictionary();
     children_[i]->AsValueInto(state);
     state->EndDictionary();
@@ skipping 172 matching lines @@
            .layer_transforms_should_scale_layer_contents) {
     return default_scale;
   }
 
   gfx::Vector2dF transform_scales = MathUtil::ComputeTransform2dScaleComponents(
       DrawTransform(), default_scale);
   return std::max(transform_scales.x(), transform_scales.y());
 }
 
 }  // namespace cc