cc: Only make num_threads - 1 SkPicture clones.

cc/output/direct_renderer.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/output/direct_renderer.h"
 
 #include <utility>
 #include <vector>
 
 #include "base/containers/hash_tables.h"
 #include "base/containers/scoped_ptr_hash_map.h"
 #include "base/debug/trace_event.h"
 #include "base/metrics/histogram.h"
 #include "cc/base/math_util.h"
 #include "cc/output/copy_output_request.h"
 #include "cc/quads/draw_quad.h"
+#include "cc/resources/raster_worker_pool.h"
 #include "ui/gfx/rect_conversions.h"
 #include "ui/gfx/transform.h"
 
 static gfx::Transform OrthoProjectionMatrix(float left,
                                             float right,
                                             float bottom,
                                             float top) {
   // Use the standard formula to map the clipping frustum to the cube from
   // [-1, -1, -1] to [1, 1, 1].
   float delta_x = right - left;
@@ skipping 383 matching lines @@
   size.Enlarge(enlarge_pass_texture_amount_.x(),
                enlarge_pass_texture_amount_.y());
   if (!texture->id())
     texture->Allocate(
         size, ResourceProvider::TextureUsageFramebuffer, RGBA_8888);
   DCHECK(texture->id());
 
   return BindFramebufferToTexture(frame, texture, render_pass->output_rect);
 }
 
+void DirectRenderer::RunOnDemandRasterTask(
+    internal::Task* on_demand_raster_task) {
+  internal::TaskGraphRunner* task_graph_runner =
+      RasterWorkerPool::GetTaskGraphRunner();
+  DCHECK(task_graph_runner);
+
+  // Make sure we have a unique task namespace token.
+  if (!on_demand_task_namespace_.IsValid())
+    on_demand_task_namespace_ = task_graph_runner->GetNamespaceToken();
+
+  // Construct a task graph that contains this single raster task.
+  internal::TaskGraph graph;
+  graph.nodes.push_back(
+      internal::TaskGraph::Node(on_demand_raster_task,
+                                RasterWorkerPool::kOnDemandRasterTaskPriority,
+                                0u));
+
+  // Schedule task and wait for task graph runner to finish running it.
+  task_graph_runner->SetTaskGraph(on_demand_task_namespace_, &graph);
+  task_graph_runner->WaitForTasksToFinishRunning(on_demand_task_namespace_);
+
+  // Collect task now that it has finished running.
+  internal::Task::Vector completed_tasks;
+  task_graph_runner->CollectCompletedTasks(on_demand_task_namespace_,
+                                           &completed_tasks);
+  DCHECK_EQ(1u, completed_tasks.size());
+  DCHECK_EQ(completed_tasks[0], on_demand_raster_task);
+}
+
 bool DirectRenderer::HasAllocatedResourcesForTesting(RenderPass::Id id)
     const {
   ScopedResource* texture = render_pass_textures_.get(id);
   return texture && texture->id();
 }
 
 // static
 gfx::Size DirectRenderer::RenderPassTextureSize(const RenderPass* render_pass) {
   return render_pass->output_rect.size();
 }
 
 }  // namespace cc