cc: Simplify task and its derived classes.

content/renderer/raster_worker_pool.h

Index: content/renderer/raster_worker_pool.h
diff --git a/content/renderer/raster_worker_pool.h b/content/renderer/raster_worker_pool.h
index b4ddf9a61c251e6f759400ccff94266941a2f604..bdc6067df4dd6f13aa125f08d8384ca17704f04b 100644
--- a/content/renderer/raster_worker_pool.h
+++ b/content/renderer/raster_worker_pool.h
@@ -43,8 +43,9 @@ class CONTENT_EXPORT RasterWorkerPool : public base::TaskRunner,
   cc::NamespaceToken GetNamespaceToken() override;
   void ScheduleTasks(cc::NamespaceToken token, cc::TaskGraph* graph) override;
   void WaitForTasksToFinishRunning(cc::NamespaceToken token) override;
-  void CollectCompletedTasks(cc::NamespaceToken token,
-                             cc::Task::Vector* completed_tasks) override;
+  void CollectCompletedTasks(
+      cc::NamespaceToken token,
+      cc::DependencyTask::Vector* completed_tasks) override;
 
   // Runs a task from one of the provided categories. Categories listed first
   // have higher priority.
@@ -78,11 +79,13 @@ class CONTENT_EXPORT RasterWorkerPool : public base::TaskRunner,
   // Simple Task for the TaskGraphRunner that wraps a closure.
   // This class is used to schedule TaskRunner tasks on the
   // |task_graph_runner_|.
-  class ClosureTask : public cc::Task {
+  class ClosureTask : public cc::DependencyTask {
    public:
     explicit ClosureTask(const base::Closure& closure);
 
-    // Overridden from cc::Task:
+    // Overridden from cc::DependencyTask:
+    void ScheduleOnOriginThread(cc::DependencyTaskClient* client) override{};
+    void CompleteOnOriginThread(cc::DependencyTaskClient* client) override{};
     void RunOnWorkerThread() override;
 
    protected:
@@ -96,8 +99,9 @@ class CONTENT_EXPORT RasterWorkerPool : public base::TaskRunner,
 
   void ScheduleTasksWithLockAcquired(cc::NamespaceToken token,
                                      cc::TaskGraph* graph);
-  void CollectCompletedTasksWithLockAcquired(cc::NamespaceToken token,
-                                             cc::Task::Vector* completed_tasks);
+  void CollectCompletedTasksWithLockAcquired(
+      cc::NamespaceToken token,
+      cc::DependencyTask::Vector* completed_tasks);
 
   // Runs a task from one of the provided categories. Categories listed first
   // have higher priority. Returns false if there were no tasks to run.
@@ -126,12 +130,12 @@ class CONTENT_EXPORT RasterWorkerPool : public base::TaskRunner,
   // Namespace used to schedule tasks in the task graph runner.
   cc::NamespaceToken namespace_token_;
   // List of tasks currently queued up for execution.
-  cc::Task::Vector tasks_;
+  cc::DependencyTask::Vector tasks_;
   // Graph object used for scheduling tasks.
   cc::TaskGraph graph_;
   // Cached vector to avoid allocation when getting the list of complete
   // tasks.
-  cc::Task::Vector completed_tasks_;
+  cc::DependencyTask::Vector completed_tasks_;
   // Condition variables for foreground and background tasks.
   base::ConditionVariable has_ready_to_run_foreground_tasks_cv_;
   base::ConditionVariable has_ready_to_run_background_tasks_cv_;