Implement cc::FilterOperations StructTraits

cc/ipc/traits_test_service.mojom

Index: cc/ipc/traits_test_service.mojom
diff --git a/cc/ipc/traits_test_service.mojom b/cc/ipc/traits_test_service.mojom
index f8bc0daca39b7bc9867329ffd1c4c063020136c7..193a62f0df23dff824f11391239c2c19a6a3b2ce 100644
--- a/cc/ipc/traits_test_service.mojom
+++ b/cc/ipc/traits_test_service.mojom
@@ -7,6 +7,7 @@ module cc.mojom;
 import "cc/ipc/begin_frame_args.mojom";
 import "cc/ipc/compositor_frame_metadata.mojom";
 import "cc/ipc/filter_operation.mojom";
+import "cc/ipc/filter_operations.mojom";
 import "cc/ipc/render_pass_id.mojom";
 import "cc/ipc/returned_resource.mojom";
 import "cc/ipc/selection.mojom";
@@ -28,6 +29,9 @@ interface TraitsTestService {
   EchoFilterOperation(FilterOperation f) => (FilterOperation pass);
 
   [Sync]
+  EchoFilterOperations(FilterOperations f) => (FilterOperations pass);
+
+  [Sync]
   EchoRenderPassId(RenderPassId r) => (RenderPassId pass);
 
   [Sync]