[ObjC] Simplify root registry generation.
The the distinction in the output isn't worth it.
PiperOrigin-RevId: 556828871
diff --git a/objectivec/GPBStruct.pbobjc.m b/objectivec/GPBStruct.pbobjc.m
index eabd761..21f156f 100644
--- a/objectivec/GPBStruct.pbobjc.m
+++ b/objectivec/GPBStruct.pbobjc.m
@@ -33,8 +33,8 @@
@implementation GPBStructRoot
-// No extensions in the file and no imports, so no need to generate
-// +extensionRegistry.
+// No extensions in the file and no imports or none of the imports (direct or
+// indirect) defined extensions, so no need to generate +extensionRegistry.
@end