Enable use_once_callback on mojom GN rule by default

mojo/public/interfaces/bindings/tests/BUILD.gn

Index: mojo/public/interfaces/bindings/tests/BUILD.gn
diff --git a/mojo/public/interfaces/bindings/tests/BUILD.gn b/mojo/public/interfaces/bindings/tests/BUILD.gn
index 7fa34eb17f9d315c2d7acc5c8f3f803ba7445a65..9eb3bd12b778173f93e582757d012321611252bb 100644
--- a/mojo/public/interfaces/bindings/tests/BUILD.gn
+++ b/mojo/public/interfaces/bindings/tests/BUILD.gn
@@ -69,6 +69,9 @@ mojom("test_interfaces") {
     ":test_mojom_import",
     ":test_mojom_import2",
   ]
+
+  # TODO(crbug.com/714018): Convert the implementation to use OnceCallback.
+  use_once_callback = false
 }
 
 component("test_export_component") {
@@ -186,6 +189,9 @@ mojom("test_struct_traits_interfaces") {
   sources = [
     "struct_with_traits.mojom",
   ]
+
+  # TODO(crbug.com/714018): Convert the implementation to use OnceCallback.
+  use_once_callback = false
 }
 
 mojom("test_associated_interfaces") {
@@ -200,6 +206,9 @@ mojom("test_associated_interfaces") {
   public_deps = [
     ":test_interfaces",
   ]
+
+  # TODO(crbug.com/714018): Convert the implementation to use OnceCallback.
+  use_once_callback = false
 }
 
 mojom("versioning_test_service_interfaces") {
@@ -222,6 +231,9 @@ mojom("test_wtf_types") {
   sources = [
     "test_wtf_types.mojom",
   ]
+
+  # TODO(crbug.com/714018): Convert the implementation to use OnceCallback.
+  use_once_callback = false
 }
 
 mojom("test_no_sources") {