Add a comment for setAdditionalInputMethodSubtypes

    /**

     * Set additional input method subtypes. Only a process which shares the same uid with the IME

     * can add additional input method subtypes to the IME.

     * Please note that a subtype's status is stored in the system.

     * For example, enabled subtypes are remembered by the framework even after they are removed

     * by using this method. If you re-add the same subtypes again,

     * they will just get enabled. If you want to avoid such conflicts, for instance, you may

     * want to create a "different" new subtype even with the same locale and mode,

     * by changing its extra value. The different subtype won't get affected by the stored past

     * status. (You may want to take a look at {@link InputMethodSubtype#hashCode()} to refer

     * to the current implementation.)

     * @param imiId Id of InputMethodInfo which additional input method subtypes will be added to.

     * @param subtypes subtypes will be added as additional subtypes of the current input method.

     * @return true if the additional input method subtypes are successfully added.