InputTracer: Don't make WindowDispatchArgs an inner class

For consistency with other structs and definitions in the backend
interface, move WindowDispatchArgs outside of the interface class.

Bug: 210460522
Test: atest inputflinger_tests
Change-Id: I9fe98448bace259faa40b082981211fdf9b1e221
diff --git a/services/inputflinger/dispatcher/trace/AndroidInputEventProtoConverter.cpp b/services/inputflinger/dispatcher/trace/AndroidInputEventProtoConverter.cpp
index a61fa85..cee741c 100644
--- a/services/inputflinger/dispatcher/trace/AndroidInputEventProtoConverter.cpp
+++ b/services/inputflinger/dispatcher/trace/AndroidInputEventProtoConverter.cpp
@@ -72,8 +72,7 @@
 }
 
 void AndroidInputEventProtoConverter::toProtoWindowDispatchEvent(
-        const InputTracingBackendInterface::WindowDispatchArgs& args,
-        proto::AndroidWindowInputDispatchEvent& outProto) {
+        const WindowDispatchArgs& args, proto::AndroidWindowInputDispatchEvent& outProto) {
     std::visit([&](auto entry) { outProto.set_event_id(entry.id); }, args.eventEntry);
     outProto.set_vsync_id(args.vsyncId);
     outProto.set_window_id(args.windowId);