Android : Is there any legit use for @+android:id?

After I upgraded my android tools to latest version to work on API21, trying to compile my project resulted in the following error:

• update_languages_button_preference_layout.xml:2: note: did you mean to use @+id instead of @+android:id?


• update_languages_button_preference_layout.xml:2: error: creating resource for external package android: id/layout.


• update_languages_button_preference_layout.xml:2: error: Error: No resource found that matches the given name (at 'id' with value '@+android:id/layout').

The problem seems to be the line android:id="@+android:id/layout": replacing @+android:id by @+id was enough to be able to compile and run the project normally.

However, a rapid search through the whole codebase revealed a few other locations in the project where the construction android:id="@+android:id/... is used. These apparently didn't prevent the project from passing all tests, even if I can't assure they are all still in use.

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  Is there any legitimate use of android:id="@+android:id that would justify leaving those references in our xml files, and not replacing them all by @+id?

  
  


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  Why didn't they raise the same error as the first file did?