Remove vtable method class prefix with --disable-name-namespacing

Fix for #2438

Author: Supreeeme

bindgen-tests/tests/expectations/tests/disable-namespacing.rs

@@ -5,5 +5,12 @@ namespace bar {
 
 typedef int Baz;
 
+// anonymous structs should still be "namespaced"
+struct Foo {
+	struct {
+		int a;
+	} anon;
+};
+
 }
 }

bindgen-tests/tests/expectations/tests/vtable_no_namespacing.rs

@@ -0,0 +1,5 @@
+// bindgen-flags: --disable-name-namespacing
+
+struct Test_Interface {
+	virtual void Virtual_Method() = 0;
+};

bindgen-tests/tests/headers/disable-namespacing.hpp

@@ -1165,7 +1165,6 @@ impl<'a> CodeGenerator for Vtable<'a> {
                         _ => panic!("Function signature type mismatch"),
                     };
 
-                    // FIXME: Is there a canonical name without the class prepended?
                     let function_name = function_item.canonical_name(ctx);
 
                     // FIXME: Need to account for overloading with times_seen (separately from regular function path).

bindgen-tests/tests/headers/vtable_no_namespacing.hpp

@@ -883,7 +883,9 @@ impl Item {
                 true
             });
 
-        let ids: Vec<_> = if ctx.options().disable_nested_struct_naming {
+        let ids: Vec<_> = if ctx.options().disable_nested_struct_naming ||
+            ctx.options().disable_name_namespacing
+        {
             let mut ids = Vec::new();
 
             // If target is anonymous we need find its first named ancestor.