mus-gpu: Include GpuPreferences when requesting for GpuService.

services/ui/gpu/interfaces/gpu_host.mojom

Index: services/ui/gpu/interfaces/gpu_host.mojom
diff --git a/services/ui/gpu/interfaces/gpu_host.mojom b/services/ui/gpu/interfaces/gpu_host.mojom
index b4baab58165107645c3d080842aa0431a170a717..1d2b8fbb81b25fdc1ce2655bbd8194a52dc62d8c 100644
--- a/services/ui/gpu/interfaces/gpu_host.mojom
+++ b/services/ui/gpu/interfaces/gpu_host.mojom
@@ -9,6 +9,8 @@ import "gpu/ipc/common/surface_handle.mojom";
 import "services/ui/gpu/interfaces/context_lost_reason.mojom";
 import "url/mojo/url.mojom";
 
+// Communication channel from the gpu process to the gpu host. This interface
+// should never have any sync function calls.
 interface GpuHost {
   DidInitialize(gpu.mojom.GpuInfo gpu_info);
   DidCreateOffscreenContext(url.mojom.Url url);