Render more Android functions safe to execute in a batch session

Render more Android functions safe to execute in a batch session

* src/androidfns.c (Fx_display_mm_width, Fx_display_mm_height)
(Fandroid_display_monitor_attributes_list)
(Fandroid_external_storage_available_p)
(Fandroid_request_storage_access): Verify that a display
connection or service object is available.

* src/androidselect.c (Fandroid_get_clipboard)
(Fandroid_browse_url_internal, Fandroid_get_clipboard_targets)
(Fandroid_get_clipboard_data, Fandroid_notifications_notify):
Moderate tone of error messages.