Implement cc::SharedQuadState 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 d637a1fffb5df84681dbdd8d39e33a14a281939c..a88b09a769792786634cb5a3c42b3b72bdaa8456 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/render_pass_id.mojom";
 import "cc/ipc/returned_resource.mojom";
+import "cc/ipc/shared_quad_state.mojom";
 import "cc/ipc/surface_id.mojom";
 import "cc/ipc/transferable_resource.mojom";
 
@@ -19,10 +20,14 @@ interface TraitsTestService {
   [Sync]
   EchoRenderPassId(RenderPassId r) => (RenderPassId pass);
 
+
   [Sync]
   EchoReturnedResource(ReturnedResource r) => (ReturnedResource pass);
 
   [Sync]
+  EchoSharedQuadState(SharedQuadState s) => (SharedQuadState pass);
+
+  [Sync]
   EchoSurfaceId(SurfaceId s) => (SurfaceId pass);
 
   [Sync]