QDoc: Only assign overload numbers to documented functions

Functions were previously assigned numbers whether they were documented
or not. This led to links containing overload numbers that did not
reflect the number of overloads in the documentation. In the minimal
case, a single function with no visible overloads would be assigned a
number.

The extraction mark is also affected in the minimal case since the
[overload1] text is included for primary overloads.

Task-number: QTBUG-139262
Change-Id: If4678721c4899525ee9971db48f4c41c9513f464
Reviewed-by: Topi Reiniö <[email protected]>
Reviewed-by: Paul Wicking <[email protected]>
(cherry picked from commit f3b238d)
Reviewed-by: Qt Cherry-pick Bot <[email protected]>

Author: David Boddie

src/qdoc/qdoc/src/qdoc/aggregate.cpp

@@ -301,10 +301,13 @@ void Aggregate::normalizeOverloads()
                         return f1->hasDoc();
                     return (compare(f1, f2) < 0);
             });
-            // Set overload numbers
+            // Set overload numbers only if the functions are documented.
+            // They are not visible if undocumented.
             signed short n{0};
-            for (auto *fn : map_it)
-                fn->setOverloadNumber(n++);
+            for (auto *fn : map_it) {
+                if (fn->hasDoc())
+                    fn->setOverloadNumber(n++);
+            }
         }
     }