Refactor MutatorHostClient from LayerTreeHost to LayerTree.

cc/trees/layer_tree_host.cc

 // Copyright 2011 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/layer_tree_host.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 230 matching lines @@
       event_listener_properties_(),
       did_complete_scale_animation_(false),
       id_(s_layer_tree_host_sequence_number.GetNext() + 1),
       next_commit_forces_redraw_(false),
       shared_bitmap_manager_(params->shared_bitmap_manager),
       gpu_memory_buffer_manager_(params->gpu_memory_buffer_manager),
       task_graph_runner_(params->task_graph_runner),
       image_serialization_processor_(params->image_serialization_processor),
       surface_client_id_(0u),
       next_surface_sequence_(1u),
-      layer_tree_(std::move(params->animation_host)) {
+      layer_tree_(base::WrapUnique(
+          new LayerTree(std::move(params->animation_host), this))) {
   DCHECK(task_graph_runner_);
 
-  layer_tree_.animation_host()->SetMutatorHostClient(this);
-
   rendering_stats_instrumentation_->set_record_rendering_stats(
       debug_state_.RecordRenderingStats());
 }
 
 void LayerTreeHost::InitializeThreaded(
     scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
     scoped_refptr<base::SingleThreadTaskRunner> impl_task_runner,
     std::unique_ptr<BeginFrameSource> external_begin_frame_source) {
   task_runner_provider_ =
       TaskRunnerProvider::Create(main_task_runner, impl_task_runner);
@@ skipping 89 matching lines @@
 
 void LayerTreeHost::InitializeProxy(
     std::unique_ptr<Proxy> proxy,
     std::unique_ptr<BeginFrameSource> external_begin_frame_source) {
   TRACE_EVENT0("cc", "LayerTreeHost::InitializeForReal");
   DCHECK(task_runner_provider_);
 
   proxy_ = std::move(proxy);
   proxy_->Start(std::move(external_begin_frame_source));
 
-  layer_tree_.animation_host()->SetSupportsScrollAnimations(
+  layer_tree_->animation_host()->SetSupportsScrollAnimations(
       proxy_->SupportsImplScrolling());
 }
 
 LayerTreeHost::~LayerTreeHost() {
   TRACE_EVENT0("cc", "LayerTreeHost::~LayerTreeHost");
 
-  layer_tree_.animation_host()->SetMutatorHostClient(nullptr);
+  layer_tree_->animation_host()->SetMutatorHostClient(nullptr);

[Khushal, 2016/08/08 16:55:03]

This should be done in the LayerTree dtor. But you need to make sure that you
destroy the LayerTree after you set the LTH to null on the root layer, since we
have a cached pointer to the LayerTree there which is always expected when we
have a reference to the host.
I would say move this to the LayerTree and destroy the tree after setting the
host to null on the root layer. Unless there is an ordering dependency here.
+ajuma, does this sound okay?

[ajuma, 2016/08/08 17:56:34]

Sounds good.

[xingliu, 2016/08/09 20:57:04]

Done.

 
   if (root_layer_.get())
     root_layer_->SetLayerTreeHost(NULL);
 
   DCHECK(swap_promise_monitor_.empty());
 
   BreakSwapPromises(SwapPromise::COMMIT_FAILS);
 
   if (proxy_) {
     DCHECK(task_runner_provider_->IsMainThread());
@@ skipping 157 matching lines @@
     ui_resource_request_queue_.clear();
   }
 
   DCHECK(!sync_tree->ViewportSizeInvalid());
 
   sync_tree->set_has_ever_been_drawn(false);
 
   {
     TRACE_EVENT0("cc", "LayerTreeHost::PushProperties");
 
-    TreeSynchronizer::PushLayerProperties(&layer_tree_, sync_tree);
+    TreeSynchronizer::PushLayerProperties(layer_tree_.get(), sync_tree);
 
     // This must happen after synchronizing property trees and after push
     // properties, which updates property tree indices, but before animation
     // host pushes properties as animation host push properties can change
     // Animation::InEffect and we want the old InEffect value for updating
     // property tree scrolling and animation.
     sync_tree->UpdatePropertyTreeScrollingAndAnimationFromMainThread();
 
     TRACE_EVENT0("cc", "LayerTreeHost::AnimationHost::PushProperties");
     DCHECK(host_impl->animation_host());
-    layer_tree_.animation_host()->PushPropertiesTo(host_impl->animation_host());
+    layer_tree_->animation_host()->PushPropertiesTo(
+        host_impl->animation_host());
   }
 
   // This must happen after synchronizing property trees and after pushing
   // properties, which updates the clobber_active_value flag.
   sync_tree->UpdatePropertyTreeScrollOffset(&property_trees_);
 
   micro_benchmark_controller_.ScheduleImplBenchmarks(host_impl);
   property_trees_.ResetAllChangeTracking();
 }
 
@@ skipping 66 matching lines @@
   client_->DidFailToInitializeOutputSurface();
 }
 
 std::unique_ptr<LayerTreeHostImpl> LayerTreeHost::CreateLayerTreeHostImpl(
     LayerTreeHostImplClient* client) {
   DCHECK(!IsRemoteServer());
   DCHECK(task_runner_provider_->IsImplThread());
 
   const bool supports_impl_scrolling = task_runner_provider_->HasImplThread();
   std::unique_ptr<AnimationHost> animation_host_impl =
-      layer_tree_.animation_host()->CreateImplInstance(supports_impl_scrolling);
+      layer_tree_->animation_host()->CreateImplInstance(
+          supports_impl_scrolling);
 
   std::unique_ptr<LayerTreeHostImpl> host_impl = LayerTreeHostImpl::Create(
       settings_, client, task_runner_provider_.get(),
       rendering_stats_instrumentation_.get(), shared_bitmap_manager_,
       gpu_memory_buffer_manager_, task_graph_runner_,
       std::move(animation_host_impl), id_);
   host_impl->SetHasGpuRasterizationTrigger(has_gpu_rasterization_trigger_);
   host_impl->SetContentIsSuitableForGpuRasterization(
       content_is_suitable_for_gpu_rasterization_);
   shared_bitmap_manager_ = NULL;
@@ skipping 84 matching lines @@
 }
 
 void LayerTreeHost::SetNextCommitForcesRedraw() {
   next_commit_forces_redraw_ = true;
   proxy_->SetNeedsUpdateLayers();
 }
 
 void LayerTreeHost::SetAnimationEvents(
     std::unique_ptr<AnimationEvents> events) {
   DCHECK(task_runner_provider_->IsMainThread());
-  layer_tree_.animation_host()->SetAnimationEvents(std::move(events));
+  layer_tree_->animation_host()->SetAnimationEvents(std::move(events));
 }
 
 void LayerTreeHost::SetRootLayer(scoped_refptr<Layer> root_layer) {
   if (root_layer_.get() == root_layer.get())
     return;
 
   if (root_layer_.get())
     root_layer_->SetLayerTreeHost(NULL);
   root_layer_ = root_layer;
   if (root_layer_.get()) {
@@ skipping 275 matching lines @@
                                              can_render_to_separate_surface);
     draw_property_utils::FindLayersThatNeedUpdates(
         this, property_trees_.transform_tree, property_trees_.effect_tree,
         &update_layer_list);
   }
 
   for (const auto& layer : update_layer_list)
     layer->SavePaintProperties();
 
   bool content_is_suitable_for_gpu = true;
-  bool did_paint_content =
-      layer_tree_.UpdateLayers(update_layer_list, &content_is_suitable_for_gpu);
+  bool did_paint_content = layer_tree_->UpdateLayers(
+      update_layer_list, &content_is_suitable_for_gpu);
 
   if (content_is_suitable_for_gpu) {
     ++num_consecutive_frames_suitable_for_gpu_;
     if (num_consecutive_frames_suitable_for_gpu_ >=
         kNumFramesToConsiderBeforeGpuRasterization) {
       content_is_suitable_for_gpu_rasterization_ = true;
     }
   } else {
     num_consecutive_frames_suitable_for_gpu_ = 0;
     content_is_suitable_for_gpu_rasterization_ = false;
@@ skipping 78 matching lines @@
 
 void LayerTreeHost::UpdateTopControlsState(TopControlsState constraints,
                                            TopControlsState current,
                                            bool animate) {
   // Top controls are only used in threaded or remote mode.
   DCHECK(IsThreaded() || IsRemoteServer());
   proxy_->UpdateTopControlsState(constraints, current, animate);
 }
 
 void LayerTreeHost::AnimateLayers(base::TimeTicks monotonic_time) {
-  AnimationHost* animation_host = layer_tree_.animation_host();
+  AnimationHost* animation_host = layer_tree_->animation_host();
   std::unique_ptr<AnimationEvents> events = animation_host->CreateEvents();
 
   if (animation_host->AnimateLayers(monotonic_time))
     animation_host->UpdateAnimationState(true, events.get());
 
   if (!events->events_.empty())
     property_trees_.needs_rebuild = true;
 }
 
 UIResourceId LayerTreeHost::CreateUIResource(UIResourceClient* client) {
@@ skipping 142 matching lines @@
 SurfaceSequence LayerTreeHost::CreateSurfaceSequence() {
   return SurfaceSequence(surface_client_id_, next_surface_sequence_++);
 }
 
 void LayerTreeHost::SetLayerTreeMutator(
     std::unique_ptr<LayerTreeMutator> mutator) {
   proxy_->SetMutator(std::move(mutator));
 }
 
 Layer* LayerTreeHost::LayerById(int id) const {
-  return layer_tree_.LayerById(id);
-}
-
-Layer* LayerTreeHost::LayerByElementId(ElementId element_id) const {
-  ElementLayersMap::const_iterator iter = element_layers_map_.find(element_id);
-  return iter != element_layers_map_.end() ? iter->second : nullptr;
-}
-
-void LayerTreeHost::AddToElementMap(Layer* layer) {
-  if (!layer->element_id())
-    return;
-
-  element_layers_map_[layer->element_id()] = layer;
-}
-
-void LayerTreeHost::RemoveFromElementMap(Layer* layer) {
-  if (!layer->element_id())
-    return;
-
-  element_layers_map_.erase(layer->element_id());
-}
-
-bool LayerTreeHost::IsElementInList(ElementId element_id,
-                                    ElementListType list_type) const {
-  return list_type == ElementListType::ACTIVE && LayerByElementId(element_id);
-}
-
-void LayerTreeHost::SetMutatorsNeedCommit() {
-  SetNeedsCommit();
-}
-
-void LayerTreeHost::SetMutatorsNeedRebuildPropertyTrees() {
-  property_trees_.needs_rebuild = true;
-}
-
-void LayerTreeHost::SetElementFilterMutated(ElementId element_id,
-                                            ElementListType list_type,
-                                            const FilterOperations& filters) {
-  Layer* layer = LayerByElementId(element_id);
-  DCHECK(layer);
-  layer->OnFilterAnimated(filters);
-}
-
-void LayerTreeHost::SetElementOpacityMutated(ElementId element_id,
-                                             ElementListType list_type,
-                                             float opacity) {
-  Layer* layer = LayerByElementId(element_id);
-  DCHECK(layer);
-  layer->OnOpacityAnimated(opacity);
-}
-
-void LayerTreeHost::SetElementTransformMutated(
-    ElementId element_id,
-    ElementListType list_type,
-    const gfx::Transform& transform) {
-  Layer* layer = LayerByElementId(element_id);
-  DCHECK(layer);
-  layer->OnTransformAnimated(transform);
-}
-
-void LayerTreeHost::SetElementScrollOffsetMutated(
-    ElementId element_id,
-    ElementListType list_type,
-    const gfx::ScrollOffset& scroll_offset) {
-  Layer* layer = LayerByElementId(element_id);
-  DCHECK(layer);
-  layer->OnScrollOffsetAnimated(scroll_offset);
-}
-
-void LayerTreeHost::ElementTransformIsAnimatingChanged(
-    ElementId element_id,
-    ElementListType list_type,
-    AnimationChangeType change_type,
-    bool is_animating) {
-  Layer* layer = LayerByElementId(element_id);
-  if (layer) {
-    switch (change_type) {
-      case AnimationChangeType::POTENTIAL:
-        layer->OnTransformIsPotentiallyAnimatingChanged(is_animating);
-        break;
-      case AnimationChangeType::RUNNING:
-        layer->OnTransformIsCurrentlyAnimatingChanged(is_animating);
-        break;
-      case AnimationChangeType::BOTH:
-        layer->OnTransformIsPotentiallyAnimatingChanged(is_animating);
-        layer->OnTransformIsCurrentlyAnimatingChanged(is_animating);
-        break;
-    }
-  }
-}
-
-void LayerTreeHost::ElementOpacityIsAnimatingChanged(
-    ElementId element_id,
-    ElementListType list_type,
-    AnimationChangeType change_type,
-    bool is_animating) {
-  Layer* layer = LayerByElementId(element_id);
-  if (layer) {
-    switch (change_type) {
-      case AnimationChangeType::POTENTIAL:
-        layer->OnOpacityIsPotentiallyAnimatingChanged(is_animating);
-        break;
-      case AnimationChangeType::RUNNING:
-        layer->OnOpacityIsCurrentlyAnimatingChanged(is_animating);
-        break;
-      case AnimationChangeType::BOTH:
-        layer->OnOpacityIsPotentiallyAnimatingChanged(is_animating);
-        layer->OnOpacityIsCurrentlyAnimatingChanged(is_animating);
-        break;
-    }
-  }
-}
-
-void LayerTreeHost::ElementFilterIsAnimatingChanged(
-    ElementId element_id,
-    ElementListType list_type,
-    AnimationChangeType change_type,
-    bool is_animating) {
-  Layer* layer = LayerByElementId(element_id);
-  if (layer) {
-    switch (change_type) {
-      case AnimationChangeType::POTENTIAL:
-        layer->OnFilterIsPotentiallyAnimatingChanged(is_animating);
-        break;
-      case AnimationChangeType::RUNNING:
-        layer->OnFilterIsCurrentlyAnimatingChanged(is_animating);
-        break;
-      case AnimationChangeType::BOTH:
-        layer->OnFilterIsPotentiallyAnimatingChanged(is_animating);
-        layer->OnFilterIsCurrentlyAnimatingChanged(is_animating);
-        break;
-    }
-  }
-}
-
-gfx::ScrollOffset LayerTreeHost::GetScrollOffsetForAnimation(
-    ElementId element_id) const {
-  Layer* layer = LayerByElementId(element_id);
-  DCHECK(layer);
-  return layer->ScrollOffsetForAnimation();
+  return layer_tree_->LayerById(id);

[Khushal, 2016/08/08 16:55:03]

Callers can directly go to the LayerTree itself.

[xingliu, 2016/08/09 20:57:04]

Done, also move the iterators and all call sites for that. Also the templates in
tree_synchronizor

 }
 
 bool LayerTreeHost::IsSingleThreaded() const {
   DCHECK(compositor_mode_ != CompositorMode::SINGLE_THREADED ||
          !task_runner_provider_->HasImplThread());
   return compositor_mode_ == CompositorMode::SINGLE_THREADED;
 }
 
 bool LayerTreeHost::IsThreaded() const {
   DCHECK(compositor_mode_ != CompositorMode::THREADED ||
@@ skipping 43 matching lines @@
   proto->set_needs_full_tree_sync(needs_full_tree_sync_);
   proto->set_needs_meta_info_recomputation(needs_meta_info_recomputation_);
   proto->set_source_frame_number(source_frame_number_);
 
   LayerProtoConverter::SerializeLayerHierarchy(root_layer_,
                                                proto->mutable_root_layer());
 
   // Serialize the LayerTree before serializing the properties. During layer
   // property serialization, we clear the list |layer_that_should_properties_|
   // from the LayerTree.
-  layer_tree_.ToProtobuf(proto->mutable_layer_tree());
+  layer_tree_->ToProtobuf(proto->mutable_layer_tree());
 
   LayerProtoConverter::SerializeLayerProperties(this,
                                                 proto->mutable_layer_updates());
 
   std::vector<PictureData> pictures =
       engine_picture_cache_->CalculateCacheUpdateAndFlush();
   proto::PictureDataVectorToSkPicturesProto(pictures,
                                             proto->mutable_pictures());
 
   proto->set_hud_layer_id(hud_layer_ ? hud_layer_->id() : Layer::INVALID_ID);
@@ skipping 57 matching lines @@
   source_frame_number_ = proto.source_frame_number();
 
   // Layer hierarchy.
   scoped_refptr<Layer> new_root_layer =
       LayerProtoConverter::DeserializeLayerHierarchy(root_layer_,
                                                      proto.root_layer(), this);
   if (root_layer_ != new_root_layer) {
     root_layer_ = new_root_layer;
   }
 
-  layer_tree_.FromProtobuf(proto.layer_tree());
+  layer_tree_->FromProtobuf(proto.layer_tree());
 
   // Ensure ClientPictureCache contains all the necessary SkPictures before
   // deserializing the properties.
   proto::SkPictures proto_pictures = proto.pictures();
   std::vector<PictureData> pictures =
       SkPicturesProtoToPictureDataVector(proto_pictures);
   client_picture_cache_->ApplyCacheUpdate(pictures);
 
   LayerProtoConverter::DeserializeLayerProperties(root_layer_.get(),
                                                   proto.layer_updates());
@@ skipping 26 matching lines @@
       EventListenerClass::kTouchStartOrMove)] =
       static_cast<EventListenerProperties>(
           proto.touch_start_or_move_event_listener_properties());
   event_listener_properties_[static_cast<size_t>(
       EventListenerClass::kTouchEndOrCancel)] =
       static_cast<EventListenerProperties>(
           proto.touch_end_or_cancel_event_listener_properties());
   id_ = proto.id();
   next_commit_forces_redraw_ = proto.next_commit_forces_redraw();
 
-  hud_layer_ = static_cast<HeadsUpDisplayLayer*>(
-      UpdateAndGetLayer(hud_layer_.get(), proto.hud_layer_id(), &layer_tree_));
-  overscroll_elasticity_layer_ =
-      UpdateAndGetLayer(overscroll_elasticity_layer_.get(),
-                        proto.overscroll_elasticity_layer_id(), &layer_tree_);
+  hud_layer_ = static_cast<HeadsUpDisplayLayer*>(UpdateAndGetLayer(
+      hud_layer_.get(), proto.hud_layer_id(), layer_tree_.get()));
+  overscroll_elasticity_layer_ = UpdateAndGetLayer(
+      overscroll_elasticity_layer_.get(),
+      proto.overscroll_elasticity_layer_id(), layer_tree_.get());
   page_scale_layer_ = UpdateAndGetLayer(
-      page_scale_layer_.get(), proto.page_scale_layer_id(), &layer_tree_);
-  inner_viewport_scroll_layer_ =
-      UpdateAndGetLayer(inner_viewport_scroll_layer_.get(),
-                        proto.inner_viewport_scroll_layer_id(), &layer_tree_);
-  outer_viewport_scroll_layer_ =
-      UpdateAndGetLayer(outer_viewport_scroll_layer_.get(),
-                        proto.outer_viewport_scroll_layer_id(), &layer_tree_);
+      page_scale_layer_.get(), proto.page_scale_layer_id(), layer_tree_.get());
+  inner_viewport_scroll_layer_ = UpdateAndGetLayer(
+      inner_viewport_scroll_layer_.get(),
+      proto.inner_viewport_scroll_layer_id(), layer_tree_.get());
+  outer_viewport_scroll_layer_ = UpdateAndGetLayer(
+      outer_viewport_scroll_layer_.get(),
+      proto.outer_viewport_scroll_layer_id(), layer_tree_.get());
 
   LayerSelectionFromProtobuf(&selection_, proto.selection());
 
   // It is required to create new PropertyTrees before deserializing it.
   property_trees_ = PropertyTrees();
   property_trees_.FromProtobuf(proto.property_trees());
 
   // Forcefully override the sequence number of all layers in the tree to have
   // a valid sequence number. Changing the sequence number for a layer does not
   // need a commit, so the value will become out of date for layers that are not
   // updated for other reasons. All layers that at this point are part of the
   // layer tree are valid, so it is OK that they have a valid sequence number.
   int seq_num = property_trees_.sequence_number;
   LayerTreeHostCommon::CallFunctionForEveryLayer(this, [seq_num](Layer* layer) {
     layer->set_property_tree_sequence_number(seq_num);
   });
 
   surface_client_id_ = proto.surface_client_id();
   next_surface_sequence_ = proto.next_surface_sequence();
 }
 
 AnimationHost* LayerTreeHost::animation_host() const {
-  return layer_tree_.animation_host();
+  return layer_tree_->animation_host();

[Khushal, 2016/08/08 16:55:02]

While we are at it, may be we can remove the methods that are simply delegating
to the LayerTree now and have callers use the LayerTree itself.

[xingliu, 2016/08/09 20:57:04]

Done, also fix the call sites.

 }
 
 }  // namespace cc