TaskGraphRunner Group support

cc/raster/tile_task_worker_pool_perftest.cc

Index: cc/raster/tile_task_worker_pool_perftest.cc
diff --git a/cc/raster/tile_task_worker_pool_perftest.cc b/cc/raster/tile_task_worker_pool_perftest.cc
index 70902c845c8293521d05ca4cf7829a0b228f60a4..32be8350d46a4e1b88c808b1d25532ae48f9cfd5 100644
--- a/cc/raster/tile_task_worker_pool_perftest.cc
+++ b/cc/raster/tile_task_worker_pool_perftest.cc
@@ -216,20 +216,21 @@ class TileTaskWorkerPoolPerfTestBase {
 
   void BuildTileTaskGraph(TaskGraph* graph,
                           const RasterTaskVector& raster_tasks) {
-    size_t priority = 0;
+    uint16_t priority = 0;
 
     for (auto& raster_task : raster_tasks) {
       priority++;
 
       for (auto& decode_task : raster_task->dependencies()) {
         graph->nodes.push_back(
-            TaskGraph::Node(decode_task.get(), priority, 0u));
+            TaskGraph::Node(decode_task.get(), 0u /* group */, priority, 0u));
         graph->edges.push_back(
             TaskGraph::Edge(raster_task.get(), decode_task.get()));
       }
 
       graph->nodes.push_back(TaskGraph::Node(
-          raster_task.get(), priority, raster_task->dependencies().size()));
+          raster_task.get(), 0u /* group */, priority,
+          static_cast<uint32_t>(raster_task->dependencies().size())));
     }
   }