Roll Chrome into Mojo.

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index d3f88039000feb2799011ce3cdf26938da1c32ed..66ee020caf36ba09d39354709858d41e9162f4a4 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -49,6 +49,7 @@
 #include "cc/quads/texture_draw_quad.h"
 #include "cc/resources/bitmap_tile_task_worker_pool.h"
 #include "cc/resources/eviction_tile_priority_queue.h"
+#include "cc/resources/gpu_rasterizer.h"
 #include "cc/resources/gpu_tile_task_worker_pool.h"
 #include "cc/resources/memory_history.h"
 #include "cc/resources/one_copy_tile_task_worker_pool.h"
@@ -57,6 +58,7 @@
 #include "cc/resources/prioritized_resource_manager.h"
 #include "cc/resources/raster_tile_priority_queue.h"
 #include "cc/resources/resource_pool.h"
+#include "cc/resources/software_rasterizer.h"
 #include "cc/resources/texture_mailbox_deleter.h"
 #include "cc/resources/tile_task_worker_pool.h"
 #include "cc/resources/ui_resource_bitmap.h"
@@ -474,8 +476,10 @@ LayerTreeHostImpl::CreateLatencyInfoSwapPromiseMonitor(
 
 ScrollElasticityHelper* LayerTreeHostImpl::CreateScrollElasticityHelper() {
   DCHECK(!scroll_elasticity_helper_);
-  scroll_elasticity_helper_.reset(
-      ScrollElasticityHelper::CreateForLayerTreeHostImpl(this));
+  if (settings_.enable_elastic_overscroll) {
+    scroll_elasticity_helper_.reset(
+        ScrollElasticityHelper::CreateForLayerTreeHostImpl(this));
+  }
   return scroll_elasticity_helper_.get();
 }
 
@@ -1057,18 +1061,18 @@ DrawResult LayerTreeHostImpl::PrepareToDraw(FrameData* frame) {
   if (input_handler_client_)
     input_handler_client_->ReconcileElasticOverscrollAndRootScroll();
 
-  // This will cause NotifyTileStateChanged() to be called for any visible tiles
-  // that completed, which will add damage to the frame for them so they appear
-  // as part of the current frame being drawn.
-  if (settings().impl_side_painting)
-    tile_manager_->UpdateVisibleTiles();
-
   UMA_HISTOGRAM_CUSTOM_COUNTS(
       "Compositing.NumActiveLayers", active_tree_->NumLayers(), 1, 400, 20);
 
   bool ok = active_tree_->UpdateDrawProperties();
   DCHECK(ok) << "UpdateDrawProperties failed during draw";
 
+  // This will cause NotifyTileStateChanged() to be called for any visible tiles
+  // that completed, which will add damage to the frame for them so they appear
+  // as part of the current frame being drawn.
+  if (settings().impl_side_painting)
+    tile_manager_->UpdateVisibleTiles(global_tile_state_);
+
   frame->render_surface_layer_list = &active_tree_->RenderSurfaceLayerList();
   frame->render_passes.clear();
   frame->render_passes_by_id.clear();
@@ -1815,8 +1819,13 @@ void LayerTreeHostImpl::ActivateSyncTree() {
 
   active_tree_->DidBecomeActive();
   ActivateAnimations();
-  if (settings_.impl_side_painting)
+  if (settings_.impl_side_painting) {
     client_->RenewTreePriority();
+    // If we have any picture layers, then by activating we also modified tile
+    // priorities.
+    if (!picture_layers_.empty())
+      DidModifyTilePriorities();
+  }
 
   client_->OnCanDrawStateChanged(CanDraw());
   client_->DidActivateSyncTree();
@@ -1956,6 +1965,7 @@ void LayerTreeHostImpl::CreateAndSetTileManager() {
   DCHECK(output_surface_);
   DCHECK(resource_provider_);
 
+  rasterizer_ = CreateRasterizer();
   CreateResourceAndTileTaskWorkerPool(&tile_task_worker_pool_, &resource_pool_,
                                       &staging_resource_pool_);
   DCHECK(tile_task_worker_pool_);
@@ -1968,13 +1978,23 @@ void LayerTreeHostImpl::CreateAndSetTileManager() {
   size_t scheduled_raster_task_limit =
       IsSynchronousSingleThreaded() ? std::numeric_limits<size_t>::max()
                                     : settings_.scheduled_raster_task_limit;
-  tile_manager_ = TileManager::Create(
-      this, task_runner, resource_pool_.get(),
-      tile_task_worker_pool_->AsTileTaskRunner(), scheduled_raster_task_limit);
+  tile_manager_ =
+      TileManager::Create(this, task_runner, resource_pool_.get(),
+                          tile_task_worker_pool_->AsTileTaskRunner(),
+                          rasterizer_.get(), scheduled_raster_task_limit);
 
   UpdateTileManagerMemoryPolicy(ActualManagedMemoryPolicy());
 }
 
+scoped_ptr<Rasterizer> LayerTreeHostImpl::CreateRasterizer() {
+  ContextProvider* context_provider = output_surface_->context_provider();
+  if (use_gpu_rasterization_ && context_provider) {
+    return GpuRasterizer::Create(context_provider, resource_provider_.get(),
+                                 settings_.use_distance_field_text, false);
+  }
+  return SoftwareRasterizer::Create();
+}
+
 void LayerTreeHostImpl::CreateResourceAndTileTaskWorkerPool(
     scoped_ptr<TileTaskWorkerPool>* tile_task_worker_pool,
     scoped_ptr<ResourcePool>* resource_pool,
@@ -2004,8 +2024,7 @@ void LayerTreeHostImpl::CreateResourceAndTileTaskWorkerPool(
                              resource_provider_->best_texture_format());
 
     *tile_task_worker_pool = GpuTileTaskWorkerPool::Create(
-        task_runner, context_provider, resource_provider_.get(),
-        settings_.use_distance_field_text);
+        task_runner, TileTaskWorkerPool::GetTaskGraphRunner());
     return;
   }
 
@@ -2070,6 +2089,7 @@ void LayerTreeHostImpl::DestroyTileManager() {
   resource_pool_ = nullptr;
   staging_resource_pool_ = nullptr;
   tile_task_worker_pool_ = nullptr;
+  rasterizer_ = nullptr;
   single_thread_synchronous_task_graph_runner_ = nullptr;
 }