cc: Generalize raster task notifications

cc/resources/image_raster_worker_pool.h

Index: cc/resources/image_raster_worker_pool.h
diff --git a/cc/resources/image_raster_worker_pool.h b/cc/resources/image_raster_worker_pool.h
index ca0bbc26a1e867a419047809da286e355318fe2d..daa013384dc534e5eca7d236bed95a2c86a0cbd5 100644
--- a/cc/resources/image_raster_worker_pool.h
+++ b/cc/resources/image_raster_worker_pool.h
@@ -49,8 +49,7 @@ class CC_EXPORT ImageRasterWorkerPool : public RasterWorkerPool,
                         ResourceProvider* resource_provider);
 
  private:
-  void OnRasterFinished();
-  void OnRasterRequiredForActivationFinished();
+  void OnRasterFinished(TaskSet task_set);
   scoped_refptr<base::debug::ConvertableToTraceFormat> StateAsValue() const;
 
   scoped_refptr<base::SequencedTaskRunner> task_runner_;
@@ -59,11 +58,9 @@ class CC_EXPORT ImageRasterWorkerPool : public RasterWorkerPool,
   RasterizerClient* client_;
   ResourceProvider* resource_provider_;
 
-  bool raster_tasks_pending_;
-  bool raster_tasks_required_for_activation_pending_;
+  TaskSetCollection raster_pending_;
 
-  scoped_refptr<RasterizerTask> raster_finished_task_;
-  scoped_refptr<RasterizerTask> raster_required_for_activation_finished_task_;
+  scoped_refptr<RasterizerTask> raster_finished_tasks_[kNumberOfTaskSets];
 
   // Task graph used when scheduling tasks and vector used to gather
   // completed tasks.