Remove parts of //cc we aren't using

cc/trees/layer_tree_impl.cc

Index: cc/trees/layer_tree_impl.cc
diff --git a/cc/trees/layer_tree_impl.cc b/cc/trees/layer_tree_impl.cc
deleted file mode 100644
index b5f8aed2307ba159c5c091f123706c768324942f..0000000000000000000000000000000000000000
--- a/cc/trees/layer_tree_impl.cc
+++ /dev/null
@@ -1,1647 +0,0 @@
-// 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_impl.h"
-
-#include <algorithm>
-#include <limits>
-#include <set>
-
-#include "base/trace_event/trace_event.h"
-#include "base/trace_event/trace_event_argument.h"
-#include "cc/animation/keyframed_animation_curve.h"
-#include "cc/animation/scrollbar_animation_controller.h"
-#include "cc/animation/scrollbar_animation_controller_linear_fade.h"
-#include "cc/animation/scrollbar_animation_controller_thinning.h"
-#include "cc/base/math_util.h"
-#include "cc/base/synced_property.h"
-#include "cc/base/util.h"
-#include "cc/debug/devtools_instrumentation.h"
-#include "cc/debug/traced_value.h"
-#include "cc/input/page_scale_animation.h"
-#include "cc/layers/heads_up_display_layer_impl.h"
-#include "cc/layers/layer.h"
-#include "cc/layers/layer_iterator.h"
-#include "cc/layers/render_surface_impl.h"
-#include "cc/layers/scrollbar_layer_impl_base.h"
-#include "cc/resources/ui_resource_request.h"
-#include "cc/trees/layer_tree_host_common.h"
-#include "cc/trees/layer_tree_host_impl.h"
-#include "cc/trees/occlusion_tracker.h"
-#include "ui/gfx/geometry/point_conversions.h"
-#include "ui/gfx/geometry/size_conversions.h"
-#include "ui/gfx/geometry/vector2d_conversions.h"
-
-namespace cc {
-
-// This class exists to split the LayerScrollOffsetDelegate between the
-// InnerViewportScrollLayer and the OuterViewportScrollLayer in a manner
-// that never requires the embedder or LayerImpl to know about.
-class LayerScrollOffsetDelegateProxy : public LayerImpl::ScrollOffsetDelegate {
- public:
-  LayerScrollOffsetDelegateProxy(LayerImpl* layer,
-                                 LayerScrollOffsetDelegate* delegate,
-                                 LayerTreeImpl* layer_tree)
-      : layer_(layer), delegate_(delegate), layer_tree_impl_(layer_tree) {}
-  virtual ~LayerScrollOffsetDelegateProxy() {}
-
-  gfx::ScrollOffset last_set_scroll_offset() const {
-    return last_set_scroll_offset_;
-  }
-
-  // LayerScrollOffsetDelegate implementation.
-  void SetCurrentScrollOffset(const gfx::ScrollOffset& new_offset) override {
-    last_set_scroll_offset_ = new_offset;
-  }
-
-  gfx::ScrollOffset GetCurrentScrollOffset() override {
-    return layer_tree_impl_->GetDelegatedScrollOffset(layer_);
-  }
-
-  bool IsExternalFlingActive() const override {
-    return delegate_->IsExternalFlingActive();
-  }
-
-  void Update() const override {
-    layer_tree_impl_->UpdateScrollOffsetDelegate();
-  }
-
- private:
-  LayerImpl* layer_;
-  LayerScrollOffsetDelegate* delegate_;
-  LayerTreeImpl* layer_tree_impl_;
-  gfx::ScrollOffset last_set_scroll_offset_;
-};
-
-LayerTreeImpl::LayerTreeImpl(
-    LayerTreeHostImpl* layer_tree_host_impl,
-    scoped_refptr<SyncedProperty<ScaleGroup>> page_scale_factor,
-    scoped_refptr<SyncedTopControls> top_controls_shown_ratio,
-    scoped_refptr<SyncedElasticOverscroll> elastic_overscroll)
-    : layer_tree_host_impl_(layer_tree_host_impl),
-      source_frame_number_(-1),
-      hud_layer_(0),
-      currently_scrolling_layer_(NULL),
-      root_layer_scroll_offset_delegate_(NULL),
-      background_color_(0),
-      has_transparent_background_(false),
-      overscroll_elasticity_layer_(NULL),
-      page_scale_layer_(NULL),
-      inner_viewport_scroll_layer_(NULL),
-      outer_viewport_scroll_layer_(NULL),
-      page_scale_factor_(page_scale_factor),
-      min_page_scale_factor_(0),
-      max_page_scale_factor_(0),
-      elastic_overscroll_(elastic_overscroll),
-      scrolling_layer_id_from_previous_tree_(0),
-      contents_textures_purged_(false),
-      viewport_size_invalid_(false),
-      needs_update_draw_properties_(true),
-      needs_full_tree_sync_(true),
-      next_activation_forces_redraw_(false),
-      has_ever_been_drawn_(false),
-      render_surface_layer_list_id_(0),
-      top_controls_shrink_blink_size_(false),
-      top_controls_height_(0),
-      top_controls_shown_ratio_(top_controls_shown_ratio) {
-}
-
-LayerTreeImpl::~LayerTreeImpl() {
-  BreakSwapPromises(SwapPromise::SWAP_FAILS);
-
-  // Need to explicitly clear the tree prior to destroying this so that
-  // the LayerTreeImpl pointer is still valid in the LayerImpl dtor.
-  DCHECK(!root_layer_);
-  DCHECK(layers_with_copy_output_request_.empty());
-}
-
-void LayerTreeImpl::Shutdown() {
-  root_layer_ = nullptr;
-}
-
-void LayerTreeImpl::ReleaseResources() {
-  if (root_layer_) {
-    LayerTreeHostCommon::CallFunctionForSubtree(
-        root_layer_.get(), [](LayerImpl* layer) { layer->ReleaseResources(); });
-  }
-}
-
-void LayerTreeImpl::RecreateResources() {
-  if (root_layer_) {
-    LayerTreeHostCommon::CallFunctionForSubtree(
-        root_layer_.get(),
-        [](LayerImpl* layer) { layer->RecreateResources(); });
-  }
-}
-
-void LayerTreeImpl::SetRootLayer(scoped_ptr<LayerImpl> layer) {
-  if (inner_viewport_scroll_layer_)
-    inner_viewport_scroll_layer_->SetScrollOffsetDelegate(NULL);
-  if (outer_viewport_scroll_layer_)
-    outer_viewport_scroll_layer_->SetScrollOffsetDelegate(NULL);
-  inner_viewport_scroll_delegate_proxy_ = nullptr;
-  outer_viewport_scroll_delegate_proxy_ = nullptr;
-
-  root_layer_ = layer.Pass();
-  currently_scrolling_layer_ = NULL;
-  inner_viewport_scroll_layer_ = NULL;
-  outer_viewport_scroll_layer_ = NULL;
-  page_scale_layer_ = NULL;
-
-  layer_tree_host_impl_->OnCanDrawStateChangedForTree();
-}
-
-LayerImpl* LayerTreeImpl::InnerViewportScrollLayer() const {
-  return inner_viewport_scroll_layer_;
-}
-
-LayerImpl* LayerTreeImpl::OuterViewportScrollLayer() const {
-  return outer_viewport_scroll_layer_;
-}
-
-gfx::ScrollOffset LayerTreeImpl::TotalScrollOffset() const {
-  gfx::ScrollOffset offset;
-
-  if (inner_viewport_scroll_layer_)
-    offset += inner_viewport_scroll_layer_->CurrentScrollOffset();
-
-  if (outer_viewport_scroll_layer_)
-    offset += outer_viewport_scroll_layer_->CurrentScrollOffset();
-
-  return offset;
-}
-
-gfx::ScrollOffset LayerTreeImpl::TotalMaxScrollOffset() const {
-  gfx::ScrollOffset offset;
-
-  if (inner_viewport_scroll_layer_)
-    offset += inner_viewport_scroll_layer_->MaxScrollOffset();
-
-  if (outer_viewport_scroll_layer_)
-    offset += outer_viewport_scroll_layer_->MaxScrollOffset();
-
-  return offset;
-}
-
-scoped_ptr<LayerImpl> LayerTreeImpl::DetachLayerTree() {
-  // Clear all data structures that have direct references to the layer tree.
-  scrolling_layer_id_from_previous_tree_ =
-    currently_scrolling_layer_ ? currently_scrolling_layer_->id() : 0;
-  if (inner_viewport_scroll_layer_)
-    inner_viewport_scroll_layer_->SetScrollOffsetDelegate(NULL);
-  if (outer_viewport_scroll_layer_)
-    outer_viewport_scroll_layer_->SetScrollOffsetDelegate(NULL);
-  inner_viewport_scroll_delegate_proxy_ = nullptr;
-  outer_viewport_scroll_delegate_proxy_ = nullptr;
-  inner_viewport_scroll_layer_ = NULL;
-  outer_viewport_scroll_layer_ = NULL;
-  page_scale_layer_ = NULL;
-  currently_scrolling_layer_ = NULL;
-
-  render_surface_layer_list_.clear();
-  set_needs_update_draw_properties();
-  return root_layer_.Pass();
-}
-
-void LayerTreeImpl::PushPropertiesTo(LayerTreeImpl* target_tree) {
-  // The request queue should have been processed and does not require a push.
-  DCHECK_EQ(ui_resource_request_queue_.size(), 0u);
-
-  if (next_activation_forces_redraw_) {
-    target_tree->ForceRedrawNextActivation();
-    next_activation_forces_redraw_ = false;
-  }
-
-  target_tree->PassSwapPromises(&swap_promise_list_);
-
-  target_tree->set_top_controls_shrink_blink_size(
-      top_controls_shrink_blink_size_);
-  target_tree->set_top_controls_height(top_controls_height_);
-  target_tree->PushTopControls(nullptr);
-
-  // Active tree already shares the page_scale_factor object with pending
-  // tree so only the limits need to be provided.
-  target_tree->PushPageScaleFactorAndLimits(nullptr, min_page_scale_factor(),
-                                            max_page_scale_factor());
-  target_tree->elastic_overscroll()->PushPendingToActive();
-
-  target_tree->pending_page_scale_animation_ =
-      pending_page_scale_animation_.Pass();
-
-  if (page_scale_layer_ && inner_viewport_scroll_layer_) {
-    target_tree->SetViewportLayersFromIds(
-        overscroll_elasticity_layer_ ? overscroll_elasticity_layer_->id()
-                                     : Layer::INVALID_ID,
-        page_scale_layer_->id(), inner_viewport_scroll_layer_->id(),
-        outer_viewport_scroll_layer_ ? outer_viewport_scroll_layer_->id()
-                                     : Layer::INVALID_ID);
-  } else {
-    target_tree->ClearViewportLayers();
-  }
-
-  target_tree->RegisterSelection(selection_start_, selection_end_);
-
-  // This should match the property synchronization in
-  // LayerTreeHost::finishCommitOnImplThread().
-  target_tree->set_source_frame_number(source_frame_number());
-  target_tree->set_background_color(background_color());
-  target_tree->set_has_transparent_background(has_transparent_background());
-
-  if (ContentsTexturesPurged())
-    target_tree->SetContentsTexturesPurged();
-  else
-    target_tree->ResetContentsTexturesPurged();
-
-  if (ViewportSizeInvalid())
-    target_tree->SetViewportSizeInvalid();
-  else
-    target_tree->ResetViewportSizeInvalid();
-
-  if (hud_layer())
-    target_tree->set_hud_layer(static_cast<HeadsUpDisplayLayerImpl*>(
-        LayerTreeHostCommon::FindLayerInSubtree(
-            target_tree->root_layer(), hud_layer()->id())));
-  else
-    target_tree->set_hud_layer(NULL);
-
-  target_tree->has_ever_been_drawn_ = false;
-}
-
-LayerImpl* LayerTreeImpl::InnerViewportContainerLayer() const {
-  return inner_viewport_scroll_layer_
-             ? inner_viewport_scroll_layer_->scroll_clip_layer()
-             : NULL;
-}
-
-LayerImpl* LayerTreeImpl::OuterViewportContainerLayer() const {
-  return outer_viewport_scroll_layer_
-             ? outer_viewport_scroll_layer_->scroll_clip_layer()
-             : NULL;
-}
-
-LayerImpl* LayerTreeImpl::CurrentlyScrollingLayer() const {
-  DCHECK(IsActiveTree());
-  return currently_scrolling_layer_;
-}
-
-void LayerTreeImpl::SetCurrentlyScrollingLayer(LayerImpl* layer) {
-  if (currently_scrolling_layer_ == layer)
-    return;
-
-  if (currently_scrolling_layer_ &&
-      currently_scrolling_layer_->scrollbar_animation_controller())
-    currently_scrolling_layer_->scrollbar_animation_controller()
-        ->DidScrollEnd();
-  currently_scrolling_layer_ = layer;
-  if (layer && layer->scrollbar_animation_controller())
-    layer->scrollbar_animation_controller()->DidScrollBegin();
-}
-
-void LayerTreeImpl::ClearCurrentlyScrollingLayer() {
-  SetCurrentlyScrollingLayer(NULL);
-  scrolling_layer_id_from_previous_tree_ = 0;
-}
-
-namespace {
-
-void ForceScrollbarParameterUpdateAfterScaleChange(LayerImpl* current_layer) {
-  if (!current_layer)
-    return;
-
-  while (current_layer) {
-    current_layer->ScrollbarParametersDidChange(false);
-    current_layer = current_layer->parent();
-  }
-}
-
-}  // namespace
-
-float LayerTreeImpl::ClampPageScaleFactorToLimits(
-    float page_scale_factor) const {
-  if (min_page_scale_factor_ && page_scale_factor < min_page_scale_factor_)
-    page_scale_factor = min_page_scale_factor_;
-  else if (max_page_scale_factor_ && page_scale_factor > max_page_scale_factor_)
-    page_scale_factor = max_page_scale_factor_;
-  return page_scale_factor;
-}
-
-void LayerTreeImpl::SetPageScaleOnActiveTree(float active_page_scale) {
-  DCHECK(IsActiveTree());
-  if (page_scale_factor()->SetCurrent(
-          ClampPageScaleFactorToLimits(active_page_scale)))
-    DidUpdatePageScale();
-}
-
-void LayerTreeImpl::PushPageScaleFromMainThread(float page_scale_factor,
-                                                float min_page_scale_factor,
-                                                float max_page_scale_factor) {
-  PushPageScaleFactorAndLimits(&page_scale_factor, min_page_scale_factor,
-                               max_page_scale_factor);
-}
-
-void LayerTreeImpl::PushPageScaleFactorAndLimits(const float* page_scale_factor,
-                                                 float min_page_scale_factor,
-                                                 float max_page_scale_factor) {
-  DCHECK(page_scale_factor || IsActiveTree());
-  bool changed_page_scale = false;
-  if (page_scale_factor) {
-    DCHECK(!IsActiveTree() || !layer_tree_host_impl_->pending_tree());
-    changed_page_scale |=
-        page_scale_factor_->PushFromMainThread(*page_scale_factor);
-  }
-  if (IsActiveTree())
-    changed_page_scale |= page_scale_factor_->PushPendingToActive();
-  changed_page_scale |=
-      SetPageScaleFactorLimits(min_page_scale_factor, max_page_scale_factor);
-
-  if (changed_page_scale)
-    DidUpdatePageScale();
-}
-
-void LayerTreeImpl::set_top_controls_shrink_blink_size(bool shrink) {
-  if (top_controls_shrink_blink_size_ == shrink)
-    return;
-
-  top_controls_shrink_blink_size_ = shrink;
-  if (IsActiveTree())
-    layer_tree_host_impl_->UpdateViewportContainerSizes();
-}
-
-void LayerTreeImpl::set_top_controls_height(float top_controls_height) {
-  if (top_controls_height_ == top_controls_height)
-    return;
-
-  top_controls_height_ = top_controls_height;
-  if (IsActiveTree())
-    layer_tree_host_impl_->UpdateViewportContainerSizes();
-}
-
-bool LayerTreeImpl::SetCurrentTopControlsShownRatio(float ratio) {
-  ratio = std::max(ratio, 0.f);
-  ratio = std::min(ratio, 1.f);
-  return top_controls_shown_ratio_->SetCurrent(ratio);
-}
-
-void LayerTreeImpl::PushTopControlsFromMainThread(
-    float top_controls_shown_ratio) {
-  PushTopControls(&top_controls_shown_ratio);
-}
-
-void LayerTreeImpl::PushTopControls(const float* top_controls_shown_ratio) {
-  DCHECK(top_controls_shown_ratio || IsActiveTree());
-
-  if (top_controls_shown_ratio) {
-    DCHECK(!IsActiveTree() || !layer_tree_host_impl_->pending_tree());
-    top_controls_shown_ratio_->PushFromMainThread(*top_controls_shown_ratio);
-  }
-  if (IsActiveTree()) {
-    if (top_controls_shown_ratio_->PushPendingToActive())
-      layer_tree_host_impl_->DidChangeTopControlsPosition();
-  }
-}
-
-bool LayerTreeImpl::SetPageScaleFactorLimits(float min_page_scale_factor,
-                                             float max_page_scale_factor) {
-  if (min_page_scale_factor == min_page_scale_factor_ &&
-      max_page_scale_factor == max_page_scale_factor_)
-    return false;
-
-  min_page_scale_factor_ = min_page_scale_factor;
-  max_page_scale_factor_ = max_page_scale_factor;
-
-  return true;
-}
-
-void LayerTreeImpl::DidUpdatePageScale() {
-  if (IsActiveTree())
-    page_scale_factor()->SetCurrent(
-        ClampPageScaleFactorToLimits(current_page_scale_factor()));
-
-  set_needs_update_draw_properties();
-
-  if (root_layer_scroll_offset_delegate_) {
-    root_layer_scroll_offset_delegate_->UpdateRootLayerState(
-        TotalScrollOffset(), TotalMaxScrollOffset(), ScrollableSize(),
-        current_page_scale_factor(), min_page_scale_factor_,
-        max_page_scale_factor_);
-  }
-
-  ForceScrollbarParameterUpdateAfterScaleChange(page_scale_layer());
-
-  HideInnerViewportScrollbarsIfNearMinimumScale();
-}
-
-void LayerTreeImpl::HideInnerViewportScrollbarsIfNearMinimumScale() {
-  if (!InnerViewportContainerLayer())
-    return;
-
-  LayerImpl::ScrollbarSet* scrollbars =
-      InnerViewportContainerLayer()->scrollbars();
-
-  if (!scrollbars)
-    return;
-
-  for (LayerImpl::ScrollbarSet::iterator it = scrollbars->begin();
-       it != scrollbars->end();
-       ++it) {
-    ScrollbarLayerImplBase* scrollbar = *it;
-    float minimum_scale_to_show_at =
-        min_page_scale_factor() * settings().scrollbar_show_scale_threshold;
-    scrollbar->SetHideLayerAndSubtree(
-        current_page_scale_factor() < minimum_scale_to_show_at);
-  }
-}
-
-SyncedProperty<ScaleGroup>* LayerTreeImpl::page_scale_factor() {
-  return page_scale_factor_.get();
-}
-
-const SyncedProperty<ScaleGroup>* LayerTreeImpl::page_scale_factor() const {
-  return page_scale_factor_.get();
-}
-
-gfx::SizeF LayerTreeImpl::ScrollableViewportSize() const {
-  if (!InnerViewportContainerLayer())
-    return gfx::SizeF();
-
-  return gfx::ScaleSize(InnerViewportContainerLayer()->BoundsForScrolling(),
-                        1.0f / current_page_scale_factor());
-}
-
-gfx::Rect LayerTreeImpl::RootScrollLayerDeviceViewportBounds() const {
-  LayerImpl* root_scroll_layer = OuterViewportScrollLayer()
-                                     ? OuterViewportScrollLayer()
-                                     : InnerViewportScrollLayer();
-  if (!root_scroll_layer || root_scroll_layer->children().empty())
-    return gfx::Rect();
-  LayerImpl* layer = root_scroll_layer->children()[0];
-  return MathUtil::MapEnclosingClippedRect(layer->screen_space_transform(),
-                                           gfx::Rect(layer->content_bounds()));
-}
-
-void LayerTreeImpl::ApplySentScrollAndScaleDeltasFromAbortedCommit() {
-  DCHECK(IsActiveTree());
-
-  page_scale_factor()->AbortCommit();
-  top_controls_shown_ratio()->AbortCommit();
-  elastic_overscroll()->AbortCommit();
-
-  if (!root_layer())
-    return;
-
-  LayerTreeHostCommon::CallFunctionForSubtree(
-      root_layer(), [](LayerImpl* layer) {
-        layer->ApplySentScrollDeltasFromAbortedCommit();
-      });
-}
-
-void LayerTreeImpl::SetViewportLayersFromIds(
-    int overscroll_elasticity_layer_id,
-    int page_scale_layer_id,
-    int inner_viewport_scroll_layer_id,
-    int outer_viewport_scroll_layer_id) {
-  overscroll_elasticity_layer_ = LayerById(overscroll_elasticity_layer_id);
-  page_scale_layer_ = LayerById(page_scale_layer_id);
-  DCHECK(page_scale_layer_);
-
-  inner_viewport_scroll_layer_ =
-      LayerById(inner_viewport_scroll_layer_id);
-  DCHECK(inner_viewport_scroll_layer_);
-
-  outer_viewport_scroll_layer_ =
-      LayerById(outer_viewport_scroll_layer_id);
-  DCHECK(outer_viewport_scroll_layer_ ||
-         outer_viewport_scroll_layer_id == Layer::INVALID_ID);
-
-  HideInnerViewportScrollbarsIfNearMinimumScale();
-
-  if (!root_layer_scroll_offset_delegate_)
-    return;
-
-  inner_viewport_scroll_delegate_proxy_ = make_scoped_ptr(
-      new LayerScrollOffsetDelegateProxy(inner_viewport_scroll_layer_,
-                                         root_layer_scroll_offset_delegate_,
-                                         this));
-
-  if (outer_viewport_scroll_layer_)
-    outer_viewport_scroll_delegate_proxy_ = make_scoped_ptr(
-        new LayerScrollOffsetDelegateProxy(outer_viewport_scroll_layer_,
-                                           root_layer_scroll_offset_delegate_,
-                                           this));
-}
-
-void LayerTreeImpl::ClearViewportLayers() {
-  page_scale_layer_ = NULL;
-  inner_viewport_scroll_layer_ = NULL;
-  outer_viewport_scroll_layer_ = NULL;
-}
-
-bool LayerTreeImpl::UpdateDrawProperties(bool update_lcd_text) {
-  if (!needs_update_draw_properties_)
-    return true;
-
-  // Calling UpdateDrawProperties must clear this flag, so there can be no
-  // early outs before this.
-  needs_update_draw_properties_ = false;
-
-  // For max_texture_size.  When the renderer is re-created in
-  // CreateAndSetRenderer, the needs update draw properties flag is set
-  // again.
-  if (!layer_tree_host_impl_->renderer())
-    return false;
-
-  // Clear this after the renderer early out, as it should still be
-  // possible to hit test even without a renderer.
-  render_surface_layer_list_.clear();
-
-  if (!root_layer())
-    return false;
-
-  {
-    TRACE_EVENT2(
-        "cc", "LayerTreeImpl::UpdateDrawProperties::CalculateDrawProperties",
-        "IsActive", IsActiveTree(), "SourceFrameNumber", source_frame_number_);
-    LayerImpl* page_scale_layer =
-        page_scale_layer_ ? page_scale_layer_ : InnerViewportContainerLayer();
-    bool can_render_to_separate_surface =
-        (layer_tree_host_impl_->GetDrawMode() !=
-         DRAW_MODE_RESOURCELESS_SOFTWARE);
-
-    ++render_surface_layer_list_id_;
-    LayerTreeHostCommon::CalcDrawPropsImplInputs inputs(
-        root_layer(), DrawViewportSize(),
-        layer_tree_host_impl_->DrawTransform(), device_scale_factor(),
-        current_page_scale_factor(), page_scale_layer,
-        elastic_overscroll()->Current(IsActiveTree()),
-        overscroll_elasticity_layer_, resource_provider()->max_texture_size(),
-        settings().can_use_lcd_text, settings().layers_always_allowed_lcd_text,
-        can_render_to_separate_surface,
-        settings().layer_transforms_should_scale_layer_contents,
-        settings().verify_property_trees,
-        &render_surface_layer_list_, render_surface_layer_list_id_);
-    LayerTreeHostCommon::CalculateDrawProperties(&inputs);
-  }
-
-  {
-    TRACE_EVENT2("cc", "LayerTreeImpl::UpdateDrawProperties::Occlusion",
-                 "IsActive", IsActiveTree(), "SourceFrameNumber",
-                 source_frame_number_);
-    OcclusionTracker<LayerImpl> occlusion_tracker(
-        root_layer()->render_surface()->content_rect());
-    occlusion_tracker.set_minimum_tracking_size(
-        settings().minimum_occlusion_tracking_size);
-
-    // LayerIterator is used here instead of CallFunctionForSubtree to only
-    // UpdateTilePriorities on layers that will be visible (and thus have valid
-    // draw properties) and not because any ordering is required.
-    auto end = LayerIterator<LayerImpl>::End(&render_surface_layer_list_);
-    for (auto it = LayerIterator<LayerImpl>::Begin(&render_surface_layer_list_);
-         it != end; ++it) {
-      occlusion_tracker.EnterLayer(it);
-
-      // There are very few render targets so this should be cheap to do for
-      // each layer instead of something more complicated.
-      bool inside_replica = false;
-      LayerImpl* layer = it->render_target();
-      while (layer && !inside_replica) {
-        if (layer->render_target()->has_replica())
-          inside_replica = true;
-        layer = layer->render_target()->parent();
-      }
-
-      // Don't use occlusion if a layer will appear in a replica, since the
-      // tile raster code does not know how to look for the replica and would
-      // consider it occluded even though the replica is visible.
-      // Since occlusion is only used for browser compositor (i.e.
-      // use_occlusion_for_tile_prioritization) and it won't use replicas,
-      // this should matter not.
-
-      if (it.represents_itself()) {
-        Occlusion occlusion =
-            inside_replica ? Occlusion()
-                           : occlusion_tracker.GetCurrentOcclusionForLayer(
-                                 it->draw_transform());
-        it->draw_properties().occlusion_in_content_space = occlusion;
-      }
-
-      if (it.represents_contributing_render_surface()) {
-        // Surfaces aren't used by the tile raster code, so they can have
-        // occlusion regardless of replicas.
-        Occlusion occlusion =
-            occlusion_tracker.GetCurrentOcclusionForContributingSurface(
-                it->render_surface()->draw_transform());
-        it->render_surface()->set_occlusion_in_content_space(occlusion);
-        // Masks are used to draw the contributing surface, so should have
-        // the same occlusion as the surface (nothing inside the surface
-        // occludes them).
-        if (LayerImpl* mask = it->mask_layer()) {
-          Occlusion mask_occlusion =
-              inside_replica
-                  ? Occlusion()
-                  : occlusion_tracker.GetCurrentOcclusionForContributingSurface(
-                        it->render_surface()->draw_transform() *
-                        it->draw_transform());
-          mask->draw_properties().occlusion_in_content_space = mask_occlusion;
-        }
-        if (LayerImpl* replica = it->replica_layer()) {
-          if (LayerImpl* mask = replica->mask_layer())
-            mask->draw_properties().occlusion_in_content_space = Occlusion();
-        }
-      }
-
-      occlusion_tracker.LeaveLayer(it);
-    }
-
-    unoccluded_screen_space_region_ =
-        occlusion_tracker.ComputeVisibleRegionInScreen();
-  }
-
-  // It'd be ideal if this could be done earlier, but when the raster source
-  // is updated from the main thread during push properties, update draw
-  // properties has not occurred yet and so it's not clear whether or not the
-  // layer can or cannot use lcd text.  So, this is the cleanup pass to
-  // determine if the raster source needs to be replaced with a non-lcd
-  // raster source due to draw properties.
-  if (update_lcd_text) {
-    // TODO(enne): Make LTHI::sync_tree return this value.
-    LayerTreeImpl* sync_tree =
-        layer_tree_host_impl_->proxy()->CommitToActiveTree()
-            ? layer_tree_host_impl_->active_tree()
-            : layer_tree_host_impl_->pending_tree();
-    // If this is not the sync tree, then it is not safe to update lcd text
-    // as it causes invalidations and the tiles may be in use.
-    DCHECK_EQ(this, sync_tree);
-    for (const auto& layer : picture_layers_)
-      layer->UpdateCanUseLCDTextAfterCommit();
-  }
-
-  {
-    TRACE_EVENT_BEGIN2("cc", "LayerTreeImpl::UpdateDrawProperties::UpdateTiles",
-                       "IsActive", IsActiveTree(), "SourceFrameNumber",
-                       source_frame_number_);
-    const bool resourceless_software_draw =
-        (layer_tree_host_impl_->GetDrawMode() ==
-         DRAW_MODE_RESOURCELESS_SOFTWARE);
-    size_t layers_updated_count = 0;
-    bool tile_priorities_updated = false;
-    for (PictureLayerImpl* layer : picture_layers_) {
-      if (!layer->IsDrawnRenderSurfaceLayerListMember())
-        continue;
-      ++layers_updated_count;
-      tile_priorities_updated |= layer->UpdateTiles(resourceless_software_draw);
-    }
-
-    if (tile_priorities_updated)
-      DidModifyTilePriorities();
-
-    TRACE_EVENT_END1("cc", "LayerTreeImpl::UpdateTilePriorities",
-                     "layers_updated_count", layers_updated_count);
-  }
-
-  DCHECK(!needs_update_draw_properties_) <<
-      "CalcDrawProperties should not set_needs_update_draw_properties()";
-  return true;
-}
-
-const LayerImplList& LayerTreeImpl::RenderSurfaceLayerList() const {
-  // If this assert triggers, then the list is dirty.
-  DCHECK(!needs_update_draw_properties_);
-  return render_surface_layer_list_;
-}
-
-const Region& LayerTreeImpl::UnoccludedScreenSpaceRegion() const {
-  // If this assert triggers, then the render_surface_layer_list_ is dirty, so
-  // the unoccluded_screen_space_region_ is not valid anymore.
-  DCHECK(!needs_update_draw_properties_);
-  return unoccluded_screen_space_region_;
-}
-
-gfx::Size LayerTreeImpl::ScrollableSize() const {
-  LayerImpl* root_scroll_layer = OuterViewportScrollLayer()
-                                     ? OuterViewportScrollLayer()
-                                     : InnerViewportScrollLayer();
-  if (!root_scroll_layer || root_scroll_layer->children().empty())
-    return gfx::Size();
-  return root_scroll_layer->children()[0]->bounds();
-}
-
-LayerImpl* LayerTreeImpl::LayerById(int id) {
-  LayerIdMap::iterator iter = layer_id_map_.find(id);
-  return iter != layer_id_map_.end() ? iter->second : NULL;
-}
-
-void LayerTreeImpl::RegisterLayer(LayerImpl* layer) {
-  DCHECK(!LayerById(layer->id()));
-  layer_id_map_[layer->id()] = layer;
-}
-
-void LayerTreeImpl::UnregisterLayer(LayerImpl* layer) {
-  DCHECK(LayerById(layer->id()));
-  layer_id_map_.erase(layer->id());
-}
-
-size_t LayerTreeImpl::NumLayers() {
-  return layer_id_map_.size();
-}
-
-void LayerTreeImpl::PushPersistedState(LayerTreeImpl* pending_tree) {
-  pending_tree->SetCurrentlyScrollingLayer(
-      LayerTreeHostCommon::FindLayerInSubtree(pending_tree->root_layer(),
-          currently_scrolling_layer_ ? currently_scrolling_layer_->id() : 0));
-}
-
-void LayerTreeImpl::DidBecomeActive() {
-  if (next_activation_forces_redraw_) {
-    layer_tree_host_impl_->SetFullRootLayerDamage();
-    next_activation_forces_redraw_ = false;
-  }
-
-  if (scrolling_layer_id_from_previous_tree_) {
-    currently_scrolling_layer_ = LayerTreeHostCommon::FindLayerInSubtree(
-        root_layer(), scrolling_layer_id_from_previous_tree_);
-  }
-
-  // Always reset this flag on activation, as we would only have activated
-  // if we were in a good state.
-  layer_tree_host_impl_->ResetRequiresHighResToDraw();
-
-  if (root_layer()) {
-    LayerTreeHostCommon::CallFunctionForSubtree(
-        root_layer(), [](LayerImpl* layer) { layer->DidBecomeActive(); });
-  }
-
-  devtools_instrumentation::DidActivateLayerTree(layer_tree_host_impl_->id(),
-                                                 source_frame_number_);
-}
-
-bool LayerTreeImpl::ContentsTexturesPurged() const {
-  return contents_textures_purged_;
-}
-
-void LayerTreeImpl::SetContentsTexturesPurged() {
-  if (contents_textures_purged_)
-    return;
-  contents_textures_purged_ = true;
-  layer_tree_host_impl_->OnCanDrawStateChangedForTree();
-}
-
-void LayerTreeImpl::ResetContentsTexturesPurged() {
-  if (!contents_textures_purged_)
-    return;
-  contents_textures_purged_ = false;
-  layer_tree_host_impl_->OnCanDrawStateChangedForTree();
-}
-
-bool LayerTreeImpl::RequiresHighResToDraw() const {
-  return layer_tree_host_impl_->RequiresHighResToDraw();
-}
-
-bool LayerTreeImpl::ViewportSizeInvalid() const {
-  return viewport_size_invalid_;
-}
-
-void LayerTreeImpl::SetViewportSizeInvalid() {
-  viewport_size_invalid_ = true;
-  layer_tree_host_impl_->OnCanDrawStateChangedForTree();
-}
-
-void LayerTreeImpl::ResetViewportSizeInvalid() {
-  viewport_size_invalid_ = false;
-  layer_tree_host_impl_->OnCanDrawStateChangedForTree();
-}
-
-Proxy* LayerTreeImpl::proxy() const {
-  return layer_tree_host_impl_->proxy();
-}
-
-const LayerTreeSettings& LayerTreeImpl::settings() const {
-  return layer_tree_host_impl_->settings();
-}
-
-const LayerTreeDebugState& LayerTreeImpl::debug_state() const {
-  return layer_tree_host_impl_->debug_state();
-}
-
-const RendererCapabilitiesImpl& LayerTreeImpl::GetRendererCapabilities() const {
-  return layer_tree_host_impl_->GetRendererCapabilities();
-}
-
-ContextProvider* LayerTreeImpl::context_provider() const {
-  return output_surface()->context_provider();
-}
-
-OutputSurface* LayerTreeImpl::output_surface() const {
-  return layer_tree_host_impl_->output_surface();
-}
-
-ResourceProvider* LayerTreeImpl::resource_provider() const {
-  return layer_tree_host_impl_->resource_provider();
-}
-
-TileManager* LayerTreeImpl::tile_manager() const {
-  return layer_tree_host_impl_->tile_manager();
-}
-
-FrameRateCounter* LayerTreeImpl::frame_rate_counter() const {
-  return layer_tree_host_impl_->fps_counter();
-}
-
-PaintTimeCounter* LayerTreeImpl::paint_time_counter() const {
-  return layer_tree_host_impl_->paint_time_counter();
-}
-
-MemoryHistory* LayerTreeImpl::memory_history() const {
-  return layer_tree_host_impl_->memory_history();
-}
-
-gfx::Size LayerTreeImpl::device_viewport_size() const {
-  return layer_tree_host_impl_->device_viewport_size();
-}
-
-float LayerTreeImpl::device_scale_factor() const {
-  return layer_tree_host_impl_->device_scale_factor();
-}
-
-DebugRectHistory* LayerTreeImpl::debug_rect_history() const {
-  return layer_tree_host_impl_->debug_rect_history();
-}
-
-bool LayerTreeImpl::IsActiveTree() const {
-  return layer_tree_host_impl_->active_tree() == this;
-}
-
-bool LayerTreeImpl::IsPendingTree() const {
-  return layer_tree_host_impl_->pending_tree() == this;
-}
-
-bool LayerTreeImpl::IsRecycleTree() const {
-  return layer_tree_host_impl_->recycle_tree() == this;
-}
-
-bool LayerTreeImpl::IsSyncTree() const {
-  return layer_tree_host_impl_->sync_tree() == this;
-}
-
-LayerImpl* LayerTreeImpl::FindActiveTreeLayerById(int id) {
-  LayerTreeImpl* tree = layer_tree_host_impl_->active_tree();
-  if (!tree)
-    return NULL;
-  return tree->LayerById(id);
-}
-
-LayerImpl* LayerTreeImpl::FindPendingTreeLayerById(int id) {
-  LayerTreeImpl* tree = layer_tree_host_impl_->pending_tree();
-  if (!tree)
-    return NULL;
-  return tree->LayerById(id);
-}
-
-bool LayerTreeImpl::PinchGestureActive() const {
-  return layer_tree_host_impl_->pinch_gesture_active();
-}
-
-BeginFrameArgs LayerTreeImpl::CurrentBeginFrameArgs() const {
-  return layer_tree_host_impl_->CurrentBeginFrameArgs();
-}
-
-base::TimeDelta LayerTreeImpl::begin_impl_frame_interval() const {
-  return layer_tree_host_impl_->begin_impl_frame_interval();
-}
-
-void LayerTreeImpl::SetNeedsCommit() {
-  layer_tree_host_impl_->SetNeedsCommit();
-}
-
-gfx::Rect LayerTreeImpl::DeviceViewport() const {
-  return layer_tree_host_impl_->DeviceViewport();
-}
-
-gfx::Size LayerTreeImpl::DrawViewportSize() const {
-  return layer_tree_host_impl_->DrawViewportSize();
-}
-
-const gfx::Rect LayerTreeImpl::ViewportRectForTilePriority() const {
-  return layer_tree_host_impl_->ViewportRectForTilePriority();
-}
-
-scoped_ptr<ScrollbarAnimationController>
-LayerTreeImpl::CreateScrollbarAnimationController(LayerImpl* scrolling_layer) {
-  DCHECK(settings().scrollbar_fade_delay_ms);
-  DCHECK(settings().scrollbar_fade_duration_ms);
-  base::TimeDelta delay =
-      base::TimeDelta::FromMilliseconds(settings().scrollbar_fade_delay_ms);
-  base::TimeDelta resize_delay = base::TimeDelta::FromMilliseconds(
-      settings().scrollbar_fade_resize_delay_ms);
-  base::TimeDelta duration =
-      base::TimeDelta::FromMilliseconds(settings().scrollbar_fade_duration_ms);
-  switch (settings().scrollbar_animator) {
-    case LayerTreeSettings::LINEAR_FADE: {
-      return ScrollbarAnimationControllerLinearFade::Create(
-          scrolling_layer,
-          layer_tree_host_impl_,
-          delay,
-          resize_delay,
-          duration);
-    }
-    case LayerTreeSettings::THINNING: {
-      return ScrollbarAnimationControllerThinning::Create(scrolling_layer,
-                                                          layer_tree_host_impl_,
-                                                          delay,
-                                                          resize_delay,
-                                                          duration);
-    }
-    case LayerTreeSettings::NO_ANIMATOR:
-      NOTREACHED();
-      break;
-  }
-  return nullptr;
-}
-
-void LayerTreeImpl::DidAnimateScrollOffset() {
-  layer_tree_host_impl_->DidAnimateScrollOffset();
-}
-
-bool LayerTreeImpl::use_gpu_rasterization() const {
-  return layer_tree_host_impl_->use_gpu_rasterization();
-}
-
-GpuRasterizationStatus LayerTreeImpl::GetGpuRasterizationStatus() const {
-  return layer_tree_host_impl_->gpu_rasterization_status();
-}
-
-bool LayerTreeImpl::create_low_res_tiling() const {
-  return layer_tree_host_impl_->create_low_res_tiling();
-}
-
-void LayerTreeImpl::SetNeedsRedraw() {
-  layer_tree_host_impl_->SetNeedsRedraw();
-}
-
-AnimationRegistrar* LayerTreeImpl::GetAnimationRegistrar() const {
-  return layer_tree_host_impl_->animation_registrar();
-}
-
-void LayerTreeImpl::GetAllTilesAndPrioritiesForTracing(
-    std::map<const Tile*, TilePriority>* tile_map) const {
-  typedef LayerIterator<LayerImpl> LayerIteratorType;
-  LayerIteratorType end = LayerIteratorType::End(&render_surface_layer_list_);
-  for (LayerIteratorType it =
-           LayerIteratorType::Begin(&render_surface_layer_list_);
-       it != end;
-       ++it) {
-    if (!it.represents_itself())
-      continue;
-    LayerImpl* layer_impl = *it;
-    layer_impl->GetAllTilesAndPrioritiesForTracing(tile_map);
-  }
-}
-
-void LayerTreeImpl::AsValueInto(base::trace_event::TracedValue* state) const {
-  TracedValue::MakeDictIntoImplicitSnapshot(state, "cc::LayerTreeImpl", this);
-  state->SetInteger("source_frame_number", source_frame_number_);
-
-  state->BeginDictionary("root_layer");
-  root_layer_->AsValueInto(state);
-  state->EndDictionary();
-
-  state->BeginArray("render_surface_layer_list");
-  typedef LayerIterator<LayerImpl> LayerIteratorType;
-  LayerIteratorType end = LayerIteratorType::End(&render_surface_layer_list_);
-  for (LayerIteratorType it = LayerIteratorType::Begin(
-           &render_surface_layer_list_); it != end; ++it) {
-    if (!it.represents_itself())
-      continue;
-    TracedValue::AppendIDRef(*it, state);
-  }
-  state->EndArray();
-
-  state->BeginArray("swap_promise_trace_ids");
-  for (size_t i = 0; i < swap_promise_list_.size(); i++)
-    state->AppendDouble(swap_promise_list_[i]->TraceId());
-  state->EndArray();
-}
-
-void LayerTreeImpl::SetRootLayerScrollOffsetDelegate(
-    LayerScrollOffsetDelegate* root_layer_scroll_offset_delegate) {
-  if (root_layer_scroll_offset_delegate_ == root_layer_scroll_offset_delegate)
-    return;
-
-  if (!root_layer_scroll_offset_delegate) {
-    // Make sure we remove the proxies from their layers before
-    // releasing them.
-    if (InnerViewportScrollLayer())
-      InnerViewportScrollLayer()->SetScrollOffsetDelegate(NULL);
-    if (OuterViewportScrollLayer())
-      OuterViewportScrollLayer()->SetScrollOffsetDelegate(NULL);
-    inner_viewport_scroll_delegate_proxy_ = nullptr;
-    outer_viewport_scroll_delegate_proxy_ = nullptr;
-  }
-
-  root_layer_scroll_offset_delegate_ = root_layer_scroll_offset_delegate;
-
-  if (root_layer_scroll_offset_delegate_) {
-    root_layer_scroll_offset_delegate_->UpdateRootLayerState(
-        TotalScrollOffset(), TotalMaxScrollOffset(), ScrollableSize(),
-        current_page_scale_factor(), min_page_scale_factor(),
-        max_page_scale_factor());
-
-    if (inner_viewport_scroll_layer_) {
-      inner_viewport_scroll_delegate_proxy_ = make_scoped_ptr(
-          new LayerScrollOffsetDelegateProxy(InnerViewportScrollLayer(),
-                                             root_layer_scroll_offset_delegate_,
-                                             this));
-      inner_viewport_scroll_layer_->SetScrollOffsetDelegate(
-          inner_viewport_scroll_delegate_proxy_.get());
-    }
-
-    if (outer_viewport_scroll_layer_) {
-      outer_viewport_scroll_delegate_proxy_ = make_scoped_ptr(
-          new LayerScrollOffsetDelegateProxy(OuterViewportScrollLayer(),
-                                             root_layer_scroll_offset_delegate_,
-                                             this));
-      outer_viewport_scroll_layer_->SetScrollOffsetDelegate(
-          outer_viewport_scroll_delegate_proxy_.get());
-    }
-
-    if (inner_viewport_scroll_layer_)
-      inner_viewport_scroll_layer_->RefreshFromScrollDelegate();
-    if (outer_viewport_scroll_layer_)
-      outer_viewport_scroll_layer_->RefreshFromScrollDelegate();
-
-    if (inner_viewport_scroll_layer_)
-      UpdateScrollOffsetDelegate();
-  }
-}
-
-void LayerTreeImpl::OnRootLayerDelegatedScrollOffsetChanged() {
-  DCHECK(root_layer_scroll_offset_delegate_);
-  if (inner_viewport_scroll_layer_) {
-    inner_viewport_scroll_layer_->RefreshFromScrollDelegate();
-  }
-  if (outer_viewport_scroll_layer_) {
-    outer_viewport_scroll_layer_->RefreshFromScrollDelegate();
-  }
-}
-
-void LayerTreeImpl::UpdateScrollOffsetDelegate() {
-  DCHECK(InnerViewportScrollLayer());
-  DCHECK(!OuterViewportScrollLayer() || outer_viewport_scroll_delegate_proxy_);
-  DCHECK(root_layer_scroll_offset_delegate_);
-
-  gfx::ScrollOffset offset =
-      inner_viewport_scroll_delegate_proxy_->last_set_scroll_offset();
-
-  if (OuterViewportScrollLayer())
-    offset += outer_viewport_scroll_delegate_proxy_->last_set_scroll_offset();
-
-  root_layer_scroll_offset_delegate_->UpdateRootLayerState(
-      offset, TotalMaxScrollOffset(), ScrollableSize(),
-      current_page_scale_factor(), min_page_scale_factor(),
-      max_page_scale_factor());
-}
-
-gfx::ScrollOffset LayerTreeImpl::GetDelegatedScrollOffset(LayerImpl* layer) {
-  DCHECK(root_layer_scroll_offset_delegate_);
-  DCHECK(InnerViewportScrollLayer());
-  if (layer == InnerViewportScrollLayer() && !OuterViewportScrollLayer())
-    return root_layer_scroll_offset_delegate_->GetTotalScrollOffset();
-
-  // If we get here, we have both inner/outer viewports, and need to distribute
-  // the scroll offset between them.
-  DCHECK(inner_viewport_scroll_delegate_proxy_);
-  DCHECK(outer_viewport_scroll_delegate_proxy_);
-  gfx::ScrollOffset inner_viewport_offset =
-      inner_viewport_scroll_delegate_proxy_->last_set_scroll_offset();
-  gfx::ScrollOffset outer_viewport_offset =
-      outer_viewport_scroll_delegate_proxy_->last_set_scroll_offset();
-
-  // It may be nothing has changed.
-  gfx::ScrollOffset delegate_offset =
-      root_layer_scroll_offset_delegate_->GetTotalScrollOffset();
-  if (inner_viewport_offset + outer_viewport_offset == delegate_offset) {
-    if (layer == InnerViewportScrollLayer())
-      return inner_viewport_offset;
-    else
-      return outer_viewport_offset;
-  }
-
-  gfx::ScrollOffset max_outer_viewport_scroll_offset =
-      OuterViewportScrollLayer()->MaxScrollOffset();
-
-  outer_viewport_offset = delegate_offset - inner_viewport_offset;
-  outer_viewport_offset.SetToMin(max_outer_viewport_scroll_offset);
-  outer_viewport_offset.SetToMax(gfx::ScrollOffset());
-
-  if (layer == OuterViewportScrollLayer())
-    return outer_viewport_offset;
-
-  inner_viewport_offset = delegate_offset - outer_viewport_offset;
-
-  return inner_viewport_offset;
-}
-
-void LayerTreeImpl::QueueSwapPromise(scoped_ptr<SwapPromise> swap_promise) {
-  DCHECK(swap_promise);
-  swap_promise_list_.push_back(swap_promise.Pass());
-}
-
-void LayerTreeImpl::PassSwapPromises(
-    ScopedPtrVector<SwapPromise>* new_swap_promise) {
-  swap_promise_list_.insert_and_take(swap_promise_list_.end(),
-                                     new_swap_promise);
-  new_swap_promise->clear();
-}
-
-void LayerTreeImpl::FinishSwapPromises(CompositorFrameMetadata* metadata) {
-  for (size_t i = 0; i < swap_promise_list_.size(); i++)
-    swap_promise_list_[i]->DidSwap(metadata);
-  swap_promise_list_.clear();
-}
-
-void LayerTreeImpl::BreakSwapPromises(SwapPromise::DidNotSwapReason reason) {
-  for (size_t i = 0; i < swap_promise_list_.size(); i++)
-    swap_promise_list_[i]->DidNotSwap(reason);
-  swap_promise_list_.clear();
-}
-
-void LayerTreeImpl::DidModifyTilePriorities() {
-  layer_tree_host_impl_->DidModifyTilePriorities();
-}
-
-void LayerTreeImpl::set_ui_resource_request_queue(
-    const UIResourceRequestQueue& queue) {
-  ui_resource_request_queue_ = queue;
-}
-
-ResourceProvider::ResourceId LayerTreeImpl::ResourceIdForUIResource(
-    UIResourceId uid) const {
-  return layer_tree_host_impl_->ResourceIdForUIResource(uid);
-}
-
-bool LayerTreeImpl::IsUIResourceOpaque(UIResourceId uid) const {
-  return layer_tree_host_impl_->IsUIResourceOpaque(uid);
-}
-
-void LayerTreeImpl::ProcessUIResourceRequestQueue() {
-  for (const auto& req : ui_resource_request_queue_) {
-    switch (req.GetType()) {
-      case UIResourceRequest::UI_RESOURCE_CREATE:
-        layer_tree_host_impl_->CreateUIResource(req.GetId(), req.GetBitmap());
-        break;
-      case UIResourceRequest::UI_RESOURCE_DELETE:
-        layer_tree_host_impl_->DeleteUIResource(req.GetId());
-        break;
-      case UIResourceRequest::UI_RESOURCE_INVALID_REQUEST:
-        NOTREACHED();
-        break;
-    }
-  }
-  ui_resource_request_queue_.clear();
-
-  // If all UI resource evictions were not recreated by processing this queue,
-  // then another commit is required.
-  if (layer_tree_host_impl_->EvictedUIResourcesExist())
-    layer_tree_host_impl_->SetNeedsCommit();
-}
-
-void LayerTreeImpl::RegisterPictureLayerImpl(PictureLayerImpl* layer) {
-  DCHECK(std::find(picture_layers_.begin(), picture_layers_.end(), layer) ==
-         picture_layers_.end());
-  picture_layers_.push_back(layer);
-}
-
-void LayerTreeImpl::UnregisterPictureLayerImpl(PictureLayerImpl* layer) {
-  std::vector<PictureLayerImpl*>::iterator it =
-      std::find(picture_layers_.begin(), picture_layers_.end(), layer);
-  DCHECK(it != picture_layers_.end());
-  picture_layers_.erase(it);
-}
-
-void LayerTreeImpl::AddLayerWithCopyOutputRequest(LayerImpl* layer) {
-  // Only the active tree needs to know about layers with copy requests, as
-  // they are aborted if not serviced during draw.
-  DCHECK(IsActiveTree());
-
-  // DCHECK(std::find(layers_with_copy_output_request_.begin(),
-  //                 layers_with_copy_output_request_.end(),
-  //                 layer) == layers_with_copy_output_request_.end());
-  // TODO(danakj): Remove this once crash is found crbug.com/309777
-  for (size_t i = 0; i < layers_with_copy_output_request_.size(); ++i) {
-    CHECK(layers_with_copy_output_request_[i] != layer)
-        << i << " of " << layers_with_copy_output_request_.size();
-  }
-  layers_with_copy_output_request_.push_back(layer);
-}
-
-void LayerTreeImpl::RemoveLayerWithCopyOutputRequest(LayerImpl* layer) {
-  // Only the active tree needs to know about layers with copy requests, as
-  // they are aborted if not serviced during draw.
-  DCHECK(IsActiveTree());
-
-  std::vector<LayerImpl*>::iterator it = std::find(
-      layers_with_copy_output_request_.begin(),
-      layers_with_copy_output_request_.end(),
-      layer);
-  DCHECK(it != layers_with_copy_output_request_.end());
-  layers_with_copy_output_request_.erase(it);
-
-  // TODO(danakj): Remove this once crash is found crbug.com/309777
-  for (size_t i = 0; i < layers_with_copy_output_request_.size(); ++i) {
-    CHECK(layers_with_copy_output_request_[i] != layer)
-        << i << " of " << layers_with_copy_output_request_.size();
-  }
-}
-
-const std::vector<LayerImpl*>& LayerTreeImpl::LayersWithCopyOutputRequest()
-    const {
-  // Only the active tree needs to know about layers with copy requests, as
-  // they are aborted if not serviced during draw.
-  DCHECK(IsActiveTree());
-
-  return layers_with_copy_output_request_;
-}
-
-template <typename LayerType>
-static inline bool LayerClipsSubtree(LayerType* layer) {
-  return layer->masks_to_bounds() || layer->mask_layer();
-}
-
-static bool PointHitsRect(
-    const gfx::PointF& screen_space_point,
-    const gfx::Transform& local_space_to_screen_space_transform,
-    const gfx::RectF& local_space_rect,
-    float* distance_to_camera) {
-  // If the transform is not invertible, then assume that this point doesn't hit
-  // this rect.
-  gfx::Transform inverse_local_space_to_screen_space(
-      gfx::Transform::kSkipInitialization);
-  if (!local_space_to_screen_space_transform.GetInverse(
-          &inverse_local_space_to_screen_space))
-    return false;
-
-  // Transform the hit test point from screen space to the local space of the
-  // given rect.
-  bool clipped = false;
-  gfx::Point3F planar_point = MathUtil::ProjectPoint3D(
-      inverse_local_space_to_screen_space, screen_space_point, &clipped);
-  gfx::PointF hit_test_point_in_local_space =
-      gfx::PointF(planar_point.x(), planar_point.y());
-
-  // If ProjectPoint could not project to a valid value, then we assume that
-  // this point doesn't hit this rect.
-  if (clipped)
-    return false;
-
-  if (!local_space_rect.Contains(hit_test_point_in_local_space))
-    return false;
-
-  if (distance_to_camera) {
-    // To compute the distance to the camera, we have to take the planar point
-    // and pull it back to world space and compute the displacement along the
-    // z-axis.
-    gfx::Point3F planar_point_in_screen_space(planar_point);
-    local_space_to_screen_space_transform.TransformPoint(
-        &planar_point_in_screen_space);
-    *distance_to_camera = planar_point_in_screen_space.z();
-  }
-
-  return true;
-}
-
-static bool PointHitsRegion(const gfx::PointF& screen_space_point,
-                            const gfx::Transform& screen_space_transform,
-                            const Region& layer_space_region,
-                            float layer_content_scale_x,
-                            float layer_content_scale_y) {
-  // If the transform is not invertible, then assume that this point doesn't hit
-  // this region.
-  gfx::Transform inverse_screen_space_transform(
-      gfx::Transform::kSkipInitialization);
-  if (!screen_space_transform.GetInverse(&inverse_screen_space_transform))
-    return false;
-
-  // Transform the hit test point from screen space to the local space of the
-  // given region.
-  bool clipped = false;
-  gfx::PointF hit_test_point_in_content_space = MathUtil::ProjectPoint(
-      inverse_screen_space_transform, screen_space_point, &clipped);
-  gfx::PointF hit_test_point_in_layer_space =
-      gfx::ScalePoint(hit_test_point_in_content_space,
-                      1.f / layer_content_scale_x,
-                      1.f / layer_content_scale_y);
-
-  // If ProjectPoint could not project to a valid value, then we assume that
-  // this point doesn't hit this region.
-  if (clipped)
-    return false;
-
-  return layer_space_region.Contains(
-      gfx::ToRoundedPoint(hit_test_point_in_layer_space));
-}
-
-static const LayerImpl* GetNextClippingLayer(const LayerImpl* layer) {
-  if (layer->scroll_parent())
-    return layer->scroll_parent();
-  if (layer->clip_parent())
-    return layer->clip_parent();
-  return layer->parent();
-}
-
-static bool PointIsClippedBySurfaceOrClipRect(
-    const gfx::PointF& screen_space_point,
-    const LayerImpl* layer) {
-  // Walk up the layer tree and hit-test any render_surfaces and any layer
-  // clip rects that are active.
-  for (; layer; layer = GetNextClippingLayer(layer)) {
-    if (layer->render_surface() &&
-        !PointHitsRect(screen_space_point,
-                       layer->render_surface()->screen_space_transform(),
-                       layer->render_surface()->content_rect(),
-                       NULL))
-      return true;
-
-    if (LayerClipsSubtree(layer) &&
-        !PointHitsRect(screen_space_point,
-                       layer->screen_space_transform(),
-                       gfx::Rect(layer->content_bounds()),
-                       NULL))
-      return true;
-  }
-
-  // If we have finished walking all ancestors without having already exited,
-  // then the point is not clipped by any ancestors.
-  return false;
-}
-
-static bool PointHitsLayer(const LayerImpl* layer,
-                           const gfx::PointF& screen_space_point,
-                           float* distance_to_intersection) {
-  gfx::RectF content_rect(layer->content_bounds());
-  if (!PointHitsRect(screen_space_point,
-                     layer->screen_space_transform(),
-                     content_rect,
-                     distance_to_intersection))
-    return false;
-
-  // At this point, we think the point does hit the layer, but we need to walk
-  // up the parents to ensure that the layer was not clipped in such a way
-  // that the hit point actually should not hit the layer.
-  if (PointIsClippedBySurfaceOrClipRect(screen_space_point, layer))
-    return false;
-
-  // Skip the HUD layer.
-  if (layer == layer->layer_tree_impl()->hud_layer())
-    return false;
-
-  return true;
-}
-
-struct FindClosestMatchingLayerDataForRecursion {
-  FindClosestMatchingLayerDataForRecursion()
-      : closest_match(NULL),
-        closest_distance(-std::numeric_limits<float>::infinity()) {}
-  LayerImpl* closest_match;
-  // Note that the positive z-axis points towards the camera, so bigger means
-  // closer in this case, counterintuitively.
-  float closest_distance;
-};
-
-template <typename Functor>
-static void FindClosestMatchingLayer(
-    const gfx::PointF& screen_space_point,
-    LayerImpl* layer,
-    const Functor& func,
-    FindClosestMatchingLayerDataForRecursion* data_for_recursion) {
-  for (int i = layer->children().size() - 1; i >= 0; --i) {
-    FindClosestMatchingLayer(
-        screen_space_point, layer->children()[i], func, data_for_recursion);
-  }
-
-  float distance_to_intersection = 0.f;
-  if (func(layer) &&
-      PointHitsLayer(layer, screen_space_point, &distance_to_intersection) &&
-      ((!data_for_recursion->closest_match ||
-        distance_to_intersection > data_for_recursion->closest_distance))) {
-    data_for_recursion->closest_distance = distance_to_intersection;
-    data_for_recursion->closest_match = layer;
-  }
-}
-
-static bool ScrollsAnyDrawnRenderSurfaceLayerListMember(LayerImpl* layer) {
-  if (!layer->scrollable())
-    return false;
-  if (layer->draw_properties().layer_or_descendant_is_drawn)
-    return true;
-
-  if (!layer->scroll_children())
-    return false;
-  for (std::set<LayerImpl*>::const_iterator it =
-           layer->scroll_children()->begin();
-       it != layer->scroll_children()->end();
-       ++it) {
-    if ((*it)->draw_properties().layer_or_descendant_is_drawn)
-      return true;
-  }
-  return false;
-}
-
-struct FindScrollingLayerFunctor {
-  bool operator()(LayerImpl* layer) const {
-    return ScrollsAnyDrawnRenderSurfaceLayerListMember(layer);
-  }
-};
-
-LayerImpl* LayerTreeImpl::FindFirstScrollingLayerThatIsHitByPoint(
-    const gfx::PointF& screen_space_point) {
-  FindClosestMatchingLayerDataForRecursion data_for_recursion;
-  FindClosestMatchingLayer(screen_space_point,
-                           root_layer(),
-                           FindScrollingLayerFunctor(),
-                           &data_for_recursion);
-  return data_for_recursion.closest_match;
-}
-
-struct HitTestVisibleScrollableOrTouchableFunctor {
-  bool operator()(LayerImpl* layer) const {
-    return layer->IsDrawnRenderSurfaceLayerListMember() ||
-           ScrollsAnyDrawnRenderSurfaceLayerListMember(layer) ||
-           !layer->touch_event_handler_region().IsEmpty() ||
-           layer->have_wheel_event_handlers();
-  }
-};
-
-LayerImpl* LayerTreeImpl::FindLayerThatIsHitByPoint(
-    const gfx::PointF& screen_space_point) {
-  if (!root_layer())
-    return NULL;
-  bool update_lcd_text = false;
-  if (!UpdateDrawProperties(update_lcd_text))
-    return NULL;
-  FindClosestMatchingLayerDataForRecursion data_for_recursion;
-  FindClosestMatchingLayer(screen_space_point,
-                           root_layer(),
-                           HitTestVisibleScrollableOrTouchableFunctor(),
-                           &data_for_recursion);
-  return data_for_recursion.closest_match;
-}
-
-static bool LayerHasTouchEventHandlersAt(const gfx::PointF& screen_space_point,
-                                         LayerImpl* layer_impl) {
-  if (layer_impl->touch_event_handler_region().IsEmpty())
-    return false;
-
-  if (!PointHitsRegion(screen_space_point,
-                       layer_impl->screen_space_transform(),
-                       layer_impl->touch_event_handler_region(),
-                       layer_impl->contents_scale_x(),
-                       layer_impl->contents_scale_y()))
-    return false;
-
-  // At this point, we think the point does hit the touch event handler region
-  // on the layer, but we need to walk up the parents to ensure that the layer
-  // was not clipped in such a way that the hit point actually should not hit
-  // the layer.
-  if (PointIsClippedBySurfaceOrClipRect(screen_space_point, layer_impl))
-    return false;
-
-  return true;
-}
-
-struct FindWheelEventLayerFunctor {
-  bool operator()(LayerImpl* layer) const {
-    return layer->have_wheel_event_handlers();
-  }
-};
-
-LayerImpl* LayerTreeImpl::FindLayerWithWheelHandlerThatIsHitByPoint(
-    const gfx::PointF& screen_space_point) {
-  if (!root_layer())
-    return NULL;
-  bool update_lcd_text = false;
-  if (!UpdateDrawProperties(update_lcd_text))
-    return NULL;
-  FindWheelEventLayerFunctor func;
-  FindClosestMatchingLayerDataForRecursion data_for_recursion;
-  FindClosestMatchingLayer(screen_space_point, root_layer(), func,
-                           &data_for_recursion);
-  return data_for_recursion.closest_match;
-}
-
-struct FindTouchEventLayerFunctor {
-  bool operator()(LayerImpl* layer) const {
-    return LayerHasTouchEventHandlersAt(screen_space_point, layer);
-  }
-  const gfx::PointF screen_space_point;
-};
-
-LayerImpl* LayerTreeImpl::FindLayerThatIsHitByPointInTouchHandlerRegion(
-    const gfx::PointF& screen_space_point) {
-  if (!root_layer())
-    return NULL;
-  bool update_lcd_text = false;
-  if (!UpdateDrawProperties(update_lcd_text))
-    return NULL;
-  FindTouchEventLayerFunctor func = {screen_space_point};
-  FindClosestMatchingLayerDataForRecursion data_for_recursion;
-  FindClosestMatchingLayer(
-      screen_space_point, root_layer(), func, &data_for_recursion);
-  return data_for_recursion.closest_match;
-}
-
-void LayerTreeImpl::RegisterSelection(const LayerSelectionBound& start,
-                                      const LayerSelectionBound& end) {
-  selection_start_ = start;
-  selection_end_ = end;
-}
-
-static ViewportSelectionBound ComputeViewportSelection(
-    const LayerSelectionBound& layer_bound,
-    LayerImpl* layer,
-    float device_scale_factor) {
-  ViewportSelectionBound viewport_bound;
-  viewport_bound.type = layer_bound.type;
-
-  if (!layer || layer_bound.type == SELECTION_BOUND_EMPTY)
-    return viewport_bound;
-
-  gfx::PointF layer_scaled_top = gfx::ScalePoint(layer_bound.edge_top,
-                                                 layer->contents_scale_x(),
-                                                 layer->contents_scale_y());
-  gfx::PointF layer_scaled_bottom = gfx::ScalePoint(layer_bound.edge_bottom,
-                                                    layer->contents_scale_x(),
-                                                    layer->contents_scale_y());
-
-  bool clipped = false;
-  gfx::PointF screen_top = MathUtil::MapPoint(
-      layer->screen_space_transform(), layer_scaled_top, &clipped);
-  gfx::PointF screen_bottom = MathUtil::MapPoint(
-      layer->screen_space_transform(), layer_scaled_bottom, &clipped);
-
-  const float inv_scale = 1.f / device_scale_factor;
-  viewport_bound.edge_top = gfx::ScalePoint(screen_top, inv_scale);
-  viewport_bound.edge_bottom = gfx::ScalePoint(screen_bottom, inv_scale);
-
-  // The bottom edge point is used for visibility testing as it is the logical
-  // focal point for bound selection handles (this may change in the future).
-  // Shifting the visibility point fractionally inward ensures that neighboring
-  // or logically coincident layers aligned to integral DPI coordinates will not
-  // spuriously occlude the bound.
-  gfx::Vector2dF visibility_offset = layer_scaled_top - layer_scaled_bottom;
-  visibility_offset.Scale(device_scale_factor / visibility_offset.Length());
-  gfx::PointF visibility_point = layer_scaled_bottom + visibility_offset;
-  if (visibility_point.x() <= 0)
-    visibility_point.set_x(visibility_point.x() + device_scale_factor);
-  visibility_point = MathUtil::MapPoint(
-      layer->screen_space_transform(), visibility_point, &clipped);
-
-  float intersect_distance = 0.f;
-  viewport_bound.visible =
-      PointHitsLayer(layer, visibility_point, &intersect_distance);
-
-  return viewport_bound;
-}
-
-void LayerTreeImpl::GetViewportSelection(ViewportSelectionBound* start,
-                                         ViewportSelectionBound* end) {
-  DCHECK(start);
-  DCHECK(end);
-
-  *start = ComputeViewportSelection(
-      selection_start_,
-      selection_start_.layer_id ? LayerById(selection_start_.layer_id) : NULL,
-      device_scale_factor());
-  if (start->type == SELECTION_BOUND_CENTER ||
-      start->type == SELECTION_BOUND_EMPTY) {
-    *end = *start;
-  } else {
-    *end = ComputeViewportSelection(
-        selection_end_,
-        selection_end_.layer_id ? LayerById(selection_end_.layer_id) : NULL,
-        device_scale_factor());
-  }
-}
-
-void LayerTreeImpl::InputScrollAnimationFinished() {
-  layer_tree_host_impl_->ScrollEnd();
-}
-
-bool LayerTreeImpl::SmoothnessTakesPriority() const {
-  return layer_tree_host_impl_->GetTreePriority() == SMOOTHNESS_TAKES_PRIORITY;
-}
-
-BlockingTaskRunner* LayerTreeImpl::BlockingMainThreadTaskRunner() const {
-  return proxy()->blocking_main_thread_task_runner();
-}
-
-void LayerTreeImpl::SetPendingPageScaleAnimation(
-    scoped_ptr<PendingPageScaleAnimation> pending_animation) {
-  pending_page_scale_animation_ = pending_animation.Pass();
-}
-
-scoped_ptr<PendingPageScaleAnimation>
-    LayerTreeImpl::TakePendingPageScaleAnimation() {
-  return pending_page_scale_animation_.Pass();
-}
-
-}  // namespace cc