// 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_common.h" #include #include #include "base/containers/adapters.h" #include "base/trace_event/trace_event.h" #include "cc/base/math_util.h" #include "cc/layers/heads_up_display_layer_impl.h" #include "cc/layers/layer.h" #include "cc/layers/layer_impl.h" #include "cc/layers/layer_iterator.h" #include "cc/trees/draw_property_utils.h" #include "cc/trees/effect_node.h" #include "cc/trees/layer_tree_host.h" #include "cc/trees/layer_tree_impl.h" #include "cc/trees/property_tree_builder.h" #include "cc/trees/scroll_node.h" #include "ui/gfx/geometry/rect_conversions.h" #include "ui/gfx/geometry/vector2d_conversions.h" #include "ui/gfx/transform.h" #include "ui/gfx/transform_util.h" namespace cc { LayerTreeHostCommon::CalcDrawPropsMainInputsForTesting:: CalcDrawPropsMainInputsForTesting(Layer* root_layer, const gfx::Size& device_viewport_size, const gfx::Transform& device_transform, float device_scale_factor, float page_scale_factor, const Layer* page_scale_layer, const Layer* inner_viewport_scroll_layer, const Layer* outer_viewport_scroll_layer) : root_layer(root_layer), device_viewport_size(device_viewport_size), device_transform(device_transform), device_scale_factor(device_scale_factor), page_scale_factor(page_scale_factor), page_scale_layer(page_scale_layer), inner_viewport_scroll_layer(inner_viewport_scroll_layer), outer_viewport_scroll_layer(outer_viewport_scroll_layer) {} LayerTreeHostCommon::CalcDrawPropsMainInputsForTesting:: CalcDrawPropsMainInputsForTesting(Layer* root_layer, const gfx::Size& device_viewport_size, const gfx::Transform& device_transform) : CalcDrawPropsMainInputsForTesting(root_layer, device_viewport_size, device_transform, 1.f, 1.f, NULL, NULL, NULL) {} LayerTreeHostCommon::CalcDrawPropsMainInputsForTesting:: CalcDrawPropsMainInputsForTesting(Layer* root_layer, const gfx::Size& device_viewport_size) : CalcDrawPropsMainInputsForTesting(root_layer, device_viewport_size, gfx::Transform()) {} LayerTreeHostCommon::CalcDrawPropsImplInputs::CalcDrawPropsImplInputs( LayerImpl* root_layer, const gfx::Size& device_viewport_size, const gfx::Transform& device_transform, float device_scale_factor, float page_scale_factor, const LayerImpl* page_scale_layer, const LayerImpl* inner_viewport_scroll_layer, const LayerImpl* outer_viewport_scroll_layer, const gfx::Vector2dF& elastic_overscroll, const LayerImpl* elastic_overscroll_application_layer, int max_texture_size, bool can_render_to_separate_surface, bool can_adjust_raster_scales, bool verify_clip_tree_calculations, bool verify_visible_rect_calculations, LayerImplList* render_surface_layer_list, PropertyTrees* property_trees) : root_layer(root_layer), device_viewport_size(device_viewport_size), device_transform(device_transform), device_scale_factor(device_scale_factor), page_scale_factor(page_scale_factor), page_scale_layer(page_scale_layer), inner_viewport_scroll_layer(inner_viewport_scroll_layer), outer_viewport_scroll_layer(outer_viewport_scroll_layer), elastic_overscroll(elastic_overscroll), elastic_overscroll_application_layer( elastic_overscroll_application_layer), max_texture_size(max_texture_size), can_render_to_separate_surface(can_render_to_separate_surface), can_adjust_raster_scales(can_adjust_raster_scales), verify_clip_tree_calculations(verify_clip_tree_calculations), verify_visible_rect_calculations(verify_visible_rect_calculations), render_surface_layer_list(render_surface_layer_list), property_trees(property_trees) {} LayerTreeHostCommon::CalcDrawPropsImplInputsForTesting:: CalcDrawPropsImplInputsForTesting(LayerImpl* root_layer, const gfx::Size& device_viewport_size, const gfx::Transform& device_transform, float device_scale_factor, LayerImplList* render_surface_layer_list) : CalcDrawPropsImplInputs(root_layer, device_viewport_size, device_transform, device_scale_factor, 1.f, NULL, NULL, NULL, gfx::Vector2dF(), NULL, std::numeric_limits::max() / 2, true, false, true, true, render_surface_layer_list, GetPropertyTrees(root_layer)) { DCHECK(root_layer); DCHECK(render_surface_layer_list); } LayerTreeHostCommon::CalcDrawPropsImplInputsForTesting:: CalcDrawPropsImplInputsForTesting(LayerImpl* root_layer, const gfx::Size& device_viewport_size, const gfx::Transform& device_transform, LayerImplList* render_surface_layer_list) : CalcDrawPropsImplInputsForTesting(root_layer, device_viewport_size, device_transform, 1.f, render_surface_layer_list) {} LayerTreeHostCommon::CalcDrawPropsImplInputsForTesting:: CalcDrawPropsImplInputsForTesting(LayerImpl* root_layer, const gfx::Size& device_viewport_size, LayerImplList* render_surface_layer_list) : CalcDrawPropsImplInputsForTesting(root_layer, device_viewport_size, gfx::Transform(), 1.f, render_surface_layer_list) {} LayerTreeHostCommon::CalcDrawPropsImplInputsForTesting:: CalcDrawPropsImplInputsForTesting(LayerImpl* root_layer, const gfx::Size& device_viewport_size, float device_scale_factor, LayerImplList* render_surface_layer_list) : CalcDrawPropsImplInputsForTesting(root_layer, device_viewport_size, gfx::Transform(), device_scale_factor, render_surface_layer_list) {} LayerTreeHostCommon::ScrollUpdateInfo::ScrollUpdateInfo() : layer_id(Layer::INVALID_ID) {} bool LayerTreeHostCommon::ScrollUpdateInfo::operator==( const LayerTreeHostCommon::ScrollUpdateInfo& other) const { return layer_id == other.layer_id && scroll_delta == other.scroll_delta; } LayerTreeHostCommon::ScrollbarsUpdateInfo::ScrollbarsUpdateInfo() : layer_id(Layer::INVALID_ID), hidden(true) {} LayerTreeHostCommon::ScrollbarsUpdateInfo::ScrollbarsUpdateInfo(int layer_id, bool hidden) : layer_id(layer_id), hidden(hidden) {} bool LayerTreeHostCommon::ScrollbarsUpdateInfo::operator==( const LayerTreeHostCommon::ScrollbarsUpdateInfo& other) const { return layer_id == other.layer_id && hidden == other.hidden; } ReflectedMainFrameState::ReflectedMainFrameState() : page_scale_delta(1.0f) {} ReflectedMainFrameState::~ReflectedMainFrameState() = default; ScrollAndScaleSet::ScrollAndScaleSet() : page_scale_delta(1.f), top_controls_delta(0.f) { } ScrollAndScaleSet::~ScrollAndScaleSet() {} static inline void SetMaskLayersAreDrawnRenderSurfaceLayerListMembers( RenderSurfaceImpl* surface, PropertyTrees* property_trees) { LayerImpl* mask_layer = surface->MaskLayer(); if (mask_layer) { mask_layer->set_is_drawn_render_surface_layer_list_member(true); draw_property_utils::ComputeMaskDrawProperties(mask_layer, property_trees); } } static inline void ClearMaskLayersAreDrawnRenderSurfaceLayerListMembers( RenderSurfaceImpl* surface) { LayerImpl* mask_layer = surface->MaskLayer(); if (mask_layer) mask_layer->set_is_drawn_render_surface_layer_list_member(false); } static inline void ClearIsDrawnRenderSurfaceLayerListMember( LayerImplList* layer_list, ScrollTree* scroll_tree) { for (LayerImpl* layer : *layer_list) layer->set_is_drawn_render_surface_layer_list_member(false); } static bool CdpPerfTracingEnabled() { bool tracing_enabled; TRACE_EVENT_CATEGORY_GROUP_ENABLED("cdp.perf", &tracing_enabled); return tracing_enabled; } static float TranslationFromActiveTreeLayerScreenSpaceTransform( LayerImpl* pending_tree_layer) { LayerTreeImpl* layer_tree_impl = pending_tree_layer->layer_tree_impl(); if (layer_tree_impl) { LayerImpl* active_tree_layer = layer_tree_impl->FindActiveTreeLayerById(pending_tree_layer->id()); if (active_tree_layer) { gfx::Transform active_tree_screen_space_transform = active_tree_layer->draw_properties().screen_space_transform; if (active_tree_screen_space_transform.IsIdentity()) return 0.f; if (active_tree_screen_space_transform.ApproximatelyEqual( pending_tree_layer->draw_properties().screen_space_transform)) return 0.f; return (active_tree_layer->draw_properties() .screen_space_transform.To2dTranslation() - pending_tree_layer->draw_properties() .screen_space_transform.To2dTranslation()) .Length(); } } return 0.f; } // A layer jitters if its screen space transform is same on two successive // commits, but has changed in between the commits. CalculateLayerJitter // computes the jitter for the layer. int LayerTreeHostCommon::CalculateLayerJitter(LayerImpl* layer) { float jitter = 0.f; layer->performance_properties().translation_from_last_frame = 0.f; layer->performance_properties().last_commit_screen_space_transform = layer->draw_properties().screen_space_transform; if (!layer->visible_layer_rect().IsEmpty()) { if (layer->draw_properties().screen_space_transform.ApproximatelyEqual( layer->performance_properties() .last_commit_screen_space_transform)) { float translation_from_last_commit = TranslationFromActiveTreeLayerScreenSpaceTransform(layer); if (translation_from_last_commit > 0.f) { layer->performance_properties().num_fixed_point_hits++; layer->performance_properties().translation_from_last_frame = translation_from_last_commit; if (layer->performance_properties().num_fixed_point_hits > layer->layer_tree_impl()->kFixedPointHitsThreshold) { // Jitter = Translation from fixed point * sqrt(Area of the layer). // The square root of the area is used instead of the area to match // the dimensions of both terms on the rhs. jitter += translation_from_last_commit * sqrt(layer->visible_layer_rect().size().GetArea()); } } else { layer->performance_properties().num_fixed_point_hits = 0; } } } return jitter; } enum PropertyTreeOption { BUILD_PROPERTY_TREES_IF_NEEDED, DONT_BUILD_PROPERTY_TREES }; static void ComputeInitialRenderSurfaceLayerList( LayerTreeImpl* layer_tree_impl, PropertyTrees* property_trees, LayerImplList* render_surface_layer_list, bool can_render_to_separate_surface) { // Add all non-skipped surfaces to the initial render surface layer list. Add // all non-skipped layers to the layer list of their target surface, and // add their content rect to their target surface's accumulated content rect. for (LayerImpl* layer : *layer_tree_impl) { if (layer->render_surface()) { layer->ClearRenderSurfaceLayerList(); ClearMaskLayersAreDrawnRenderSurfaceLayerListMembers( layer->render_surface()); } layer->set_is_drawn_render_surface_layer_list_member(false); bool is_root = layer_tree_impl->IsRootLayer(layer); bool skip_layer = !is_root && draw_property_utils::LayerShouldBeSkipped( layer, property_trees->transform_tree, property_trees->effect_tree); if (skip_layer) continue; bool render_to_separate_surface = is_root || (can_render_to_separate_surface && layer->render_surface()); if (render_to_separate_surface) { DCHECK(layer->render_surface()); DCHECK(layer->render_target() == layer->render_surface()); RenderSurfaceImpl* surface = layer->render_surface(); surface->ClearAccumulatedContentRect(); render_surface_layer_list->push_back(layer); if (is_root) { // The root surface does not contribute to any other surface, it has no // target. layer->render_surface()->set_contributes_to_drawn_surface(false); } else { surface->render_target()->layer_list().push_back(layer); bool contributes_to_drawn_surface = property_trees->effect_tree.ContributesToDrawnSurface( layer->effect_tree_index()); layer->render_surface()->set_contributes_to_drawn_surface( contributes_to_drawn_surface); } draw_property_utils::ComputeSurfaceDrawProperties(property_trees, surface); // Ignore occlusion from outside the surface when surface contents need to // be fully drawn. Layers with copy-request need to be complete. We could // be smarter about layers with filters that move pixels and exclude // regions where both layers and the filters are occluded, but this seems // like overkill. // TODO(senorblanco): make this smarter for the SkImageFilter case (check // for pixel-moving filters) const FilterOperations& filters = surface->Filters(); bool is_occlusion_immune = surface->HasCopyRequest() || filters.HasReferenceFilter() || filters.HasFilterThatMovesPixels(); if (is_occlusion_immune) { surface->SetNearestOcclusionImmuneAncestor(surface); } else if (is_root) { surface->SetNearestOcclusionImmuneAncestor(nullptr); } else { surface->SetNearestOcclusionImmuneAncestor( surface->render_target()->nearest_occlusion_immune_ancestor()); } } bool layer_is_drawn = property_trees->effect_tree.Node(layer->effect_tree_index())->is_drawn; bool layer_should_be_drawn = draw_property_utils::LayerNeedsUpdate( layer, layer_is_drawn, property_trees); if (!layer_should_be_drawn) continue; layer->set_is_drawn_render_surface_layer_list_member(true); layer->render_target()->layer_list().push_back(layer); // The layer contributes its drawable content rect to its render target. layer->render_target()->AccumulateContentRectFromContributingLayer(layer); } } static void ComputeSurfaceContentRects(LayerTreeImpl* layer_tree_impl, PropertyTrees* property_trees, LayerImplList* render_surface_layer_list, int max_texture_size) { // Walk the list backwards, accumulating each surface's content rect into its // target's content rect. for (LayerImpl* layer : base::Reversed(*render_surface_layer_list)) { if (layer_tree_impl->IsRootLayer(layer)) { // The root layer's surface content rect is always the entire viewport. layer->render_surface()->SetContentRectToViewport(); continue; } RenderSurfaceImpl* surface = layer->render_surface(); // Now all contributing drawable content rect has been accumulated to this // render surface, calculate the content rect. surface->CalculateContentRectFromAccumulatedContentRect(max_texture_size); // Now the render surface's content rect is calculated correctly, it could // contribute to its render target. surface->render_target() ->AccumulateContentRectFromContributingRenderSurface(surface); } } static void ComputeListOfNonEmptySurfaces(LayerTreeImpl* layer_tree_impl, PropertyTrees* property_trees, LayerImplList* initial_surface_list, LayerImplList* final_surface_list) { // Walk the initial surface list forwards. The root surface and each // surface with a non-empty content rect go into the final render surface // layer list. Surfaces with empty content rects or whose target isn't in // the final list do not get added to the final list. for (LayerImpl* layer : *initial_surface_list) { bool is_root = layer_tree_impl->IsRootLayer(layer); RenderSurfaceImpl* surface = layer->render_surface(); RenderSurfaceImpl* target_surface = surface->render_target(); if (!is_root && (surface->content_rect().IsEmpty() || target_surface->layer_list().empty())) { ClearIsDrawnRenderSurfaceLayerListMember(&surface->layer_list(), &property_trees->scroll_tree); surface->ClearLayerLists(); if (!is_root) { LayerImplList& target_list = target_surface->layer_list(); auto it = std::find(target_list.begin(), target_list.end(), layer); if (it != target_list.end()) { target_list.erase(it); // This surface has an empty content rect. If its target's layer list // had no other layers, then its target would also have had an empty // content rect, meaning it would have been removed and had its layer // list cleared when we visited it, unless the target surface is the // root surface. DCHECK(!target_surface->layer_list().empty() || target_surface->render_target() == target_surface); } else { // This layer was removed when the target itself was cleared. DCHECK(target_surface->layer_list().empty()); } } continue; } SetMaskLayersAreDrawnRenderSurfaceLayerListMembers(surface, property_trees); final_surface_list->push_back(layer); } } static void CalculateRenderSurfaceLayerList( LayerTreeImpl* layer_tree_impl, PropertyTrees* property_trees, LayerImplList* render_surface_layer_list, const bool can_render_to_separate_surface, const int max_texture_size) { // This calculates top level Render Surface Layer List, and Layer List for all // Render Surfaces. // |render_surface_layer_list| is the top level RenderSurfaceLayerList. LayerImplList initial_render_surface_list; // First compute an RSLL that might include surfaces that later turn out to // have an empty content rect. After surface content rects are computed, // produce a final RSLL that omits empty surfaces. ComputeInitialRenderSurfaceLayerList(layer_tree_impl, property_trees, &initial_render_surface_list, can_render_to_separate_surface); ComputeSurfaceContentRects(layer_tree_impl, property_trees, &initial_render_surface_list, max_texture_size); ComputeListOfNonEmptySurfaces(layer_tree_impl, property_trees, &initial_render_surface_list, render_surface_layer_list); } void CalculateDrawPropertiesInternal( LayerTreeHostCommon::CalcDrawPropsImplInputs* inputs, PropertyTreeOption property_tree_option) { inputs->render_surface_layer_list->clear(); const bool should_measure_property_tree_performance = property_tree_option == BUILD_PROPERTY_TREES_IF_NEEDED; LayerImplList visible_layer_list; switch (property_tree_option) { case BUILD_PROPERTY_TREES_IF_NEEDED: { // The translation from layer to property trees is an intermediate // state. We will eventually get these data passed directly to the // compositor. if (should_measure_property_tree_performance) { TRACE_EVENT_BEGIN0( TRACE_DISABLED_BY_DEFAULT("cc.debug.cdp-perf"), "LayerTreeHostCommon::ComputeVisibleRectsWithPropertyTrees"); } draw_property_utils::BuildPropertyTreesAndComputeVisibleRects( inputs->root_layer, inputs->page_scale_layer, inputs->inner_viewport_scroll_layer, inputs->outer_viewport_scroll_layer, inputs->elastic_overscroll_application_layer, inputs->elastic_overscroll, inputs->page_scale_factor, inputs->device_scale_factor, gfx::Rect(inputs->device_viewport_size), inputs->device_transform, inputs->can_render_to_separate_surface, inputs->property_trees, &visible_layer_list); // Property trees are normally constructed on the main thread and // passed to compositor thread. Source to parent updates on them are not // allowed in the compositor thread. Some tests build them on the // compositor thread, so we need to explicitly disallow source to parent // updates when they are built on compositor thread. inputs->property_trees->transform_tree .set_source_to_parent_updates_allowed(false); if (should_measure_property_tree_performance) { TRACE_EVENT_END0( TRACE_DISABLED_BY_DEFAULT("cc.debug.cdp-perf"), "LayerTreeHostCommon::ComputeVisibleRectsWithPropertyTrees"); } break; } case DONT_BUILD_PROPERTY_TREES: { TRACE_EVENT0( TRACE_DISABLED_BY_DEFAULT("cc.debug.cdp-perf"), "LayerTreeHostCommon::ComputeJustVisibleRectsWithPropertyTrees"); // Since page scale and elastic overscroll are SyncedProperties, changes // on the active tree immediately affect the pending tree, so instead of // trying to update property trees whenever these values change, we // update property trees before using them. draw_property_utils::UpdatePageScaleFactor( inputs->property_trees, inputs->page_scale_layer, inputs->page_scale_factor, inputs->device_scale_factor, inputs->device_transform); draw_property_utils::UpdateElasticOverscroll( inputs->property_trees, inputs->elastic_overscroll_application_layer, inputs->elastic_overscroll); // Similarly, the device viewport and device transform are shared // by both trees. PropertyTrees* property_trees = inputs->property_trees; property_trees->clip_tree.SetViewportClip( gfx::RectF(gfx::SizeF(inputs->device_viewport_size))); float page_scale_factor_for_root = inputs->page_scale_layer == inputs->root_layer ? inputs->page_scale_factor : 1.f; property_trees->transform_tree.SetRootTransformsAndScales( inputs->device_scale_factor, page_scale_factor_for_root, inputs->device_transform, inputs->root_layer->position()); draw_property_utils::ComputeVisibleRects( inputs->root_layer, inputs->property_trees, inputs->can_render_to_separate_surface, &visible_layer_list); break; } } if (should_measure_property_tree_performance) { TRACE_EVENT_BEGIN0(TRACE_DISABLED_BY_DEFAULT("cc.debug.cdp-perf"), "LayerTreeHostCommon::CalculateDrawProperties"); } DCHECK(inputs->can_render_to_separate_surface == inputs->property_trees->non_root_surfaces_enabled); for (LayerImpl* layer : visible_layer_list) { draw_property_utils::ComputeLayerDrawProperties(layer, inputs->property_trees); } CalculateRenderSurfaceLayerList( inputs->root_layer->layer_tree_impl(), inputs->property_trees, inputs->render_surface_layer_list, inputs->can_render_to_separate_surface, inputs->max_texture_size); if (inputs->verify_clip_tree_calculations) draw_property_utils::VerifyClipTreeCalculations(visible_layer_list, inputs->property_trees); if (inputs->verify_visible_rect_calculations) draw_property_utils::VerifyVisibleRectsCalculations(visible_layer_list, inputs->property_trees); if (should_measure_property_tree_performance) { TRACE_EVENT_END0(TRACE_DISABLED_BY_DEFAULT("cc.debug.cdp-perf"), "LayerTreeHostCommon::CalculateDrawProperties"); } // A root layer render_surface should always exist after // CalculateDrawProperties. DCHECK(inputs->root_layer->render_surface()); } void LayerTreeHostCommon::CalculateDrawPropertiesForTesting( CalcDrawPropsMainInputsForTesting* inputs) { LayerList update_layer_list; bool can_render_to_separate_surface = true; PropertyTrees* property_trees = inputs->root_layer->GetLayerTree()->property_trees(); Layer* overscroll_elasticity_layer = nullptr; gfx::Vector2dF elastic_overscroll; PropertyTreeBuilder::BuildPropertyTrees( inputs->root_layer, inputs->page_scale_layer, inputs->inner_viewport_scroll_layer, inputs->outer_viewport_scroll_layer, overscroll_elasticity_layer, elastic_overscroll, inputs->page_scale_factor, inputs->device_scale_factor, gfx::Rect(inputs->device_viewport_size), inputs->device_transform, property_trees); draw_property_utils::UpdatePropertyTrees(property_trees, can_render_to_separate_surface); draw_property_utils::FindLayersThatNeedUpdates( inputs->root_layer->GetLayerTree(), property_trees, &update_layer_list); } void LayerTreeHostCommon::CalculateDrawProperties( CalcDrawPropsImplInputs* inputs) { CalculateDrawPropertiesInternal(inputs, DONT_BUILD_PROPERTY_TREES); if (CdpPerfTracingEnabled()) { LayerTreeImpl* layer_tree_impl = inputs->root_layer->layer_tree_impl(); if (layer_tree_impl->IsPendingTree() && layer_tree_impl->is_first_frame_after_commit()) { LayerImpl* active_tree_root = layer_tree_impl->FindActiveTreeLayerById(inputs->root_layer->id()); float jitter = 0.f; if (active_tree_root) { LayerImpl* last_scrolled_layer = layer_tree_impl->LayerById( active_tree_root->layer_tree_impl()->LastScrolledLayerId()); if (last_scrolled_layer) { const int last_scrolled_scroll_node_id = last_scrolled_layer->scroll_tree_index(); std::unordered_set jitter_nodes; for (auto* layer : *layer_tree_impl) { // Layers that have the same scroll tree index jitter together. So, // it is enough to calculate jitter on one of these layers. So, // after we find a jittering layer, we need not consider other // layers with the same scroll tree index. int scroll_tree_index = layer->scroll_tree_index(); if (last_scrolled_scroll_node_id <= scroll_tree_index && jitter_nodes.find(scroll_tree_index) == jitter_nodes.end()) { float layer_jitter = CalculateLayerJitter(layer); if (layer_jitter > 0.f) { jitter_nodes.insert(layer->scroll_tree_index()); jitter += layer_jitter; } } } } } TRACE_EVENT_ASYNC_BEGIN1( "cdp.perf", "jitter", inputs->root_layer->layer_tree_impl()->source_frame_number(), "value", jitter); inputs->root_layer->layer_tree_impl()->set_is_first_frame_after_commit( false); TRACE_EVENT_ASYNC_END1( "cdp.perf", "jitter", inputs->root_layer->layer_tree_impl()->source_frame_number(), "value", jitter); } } } void LayerTreeHostCommon::CalculateDrawPropertiesForTesting( CalcDrawPropsImplInputsForTesting* inputs) { PropertyTreeBuilder::PreCalculateMetaInformationForTesting( inputs->root_layer); CalculateDrawPropertiesInternal(inputs, BUILD_PROPERTY_TREES_IF_NEEDED); } PropertyTrees* GetPropertyTrees(Layer* layer) { return layer->GetLayerTree()->property_trees(); } PropertyTrees* GetPropertyTrees(LayerImpl* layer) { return layer->layer_tree_impl()->property_trees(); } } // namespace cc