cc: Add image decode queue functionality to image manager.

cc/layers/picture_layer_unittest.cc

Index: cc/layers/picture_layer_unittest.cc
diff --git a/cc/layers/picture_layer_unittest.cc b/cc/layers/picture_layer_unittest.cc
index bda0e41b916b6e750c73b9739da430a54ae561b0..98c06be642b9c07b93dd85199e583ba87ce44726 100644
--- a/cc/layers/picture_layer_unittest.cc
+++ b/cc/layers/picture_layer_unittest.cc
@@ -311,6 +311,7 @@ TEST(PictureLayerTest, NonMonotonicSourceFrameNumber) {
   params.task_graph_runner = &task_graph_runner;
   params.main_task_runner = base::ThreadTaskRunnerHandle::Get();
   params.mutator_host = animation_host.get();
+  params.image_worker_task_runner = nullptr;
   std::unique_ptr<LayerTreeHost> host1 =
       LayerTreeHostInProcess::CreateSingleThreaded(&single_thread_client,
                                                    &params);
@@ -327,6 +328,7 @@ TEST(PictureLayerTest, NonMonotonicSourceFrameNumber) {
   params2.main_task_runner = base::ThreadTaskRunnerHandle::Get();
   params2.client = &host_client2;
   params2.mutator_host = animation_host2.get();
+  params2.image_worker_task_runner = nullptr;
   std::unique_ptr<LayerTreeHost> host2 =
       LayerTreeHostInProcess::CreateSingleThreaded(&single_thread_client,
                                                    &params2);