Sync SDL3 wiki -> header

[ci skip]

include/SDL3/SDL_dialog.h

@@ -94,6 +94,10 @@ typedef struct SDL_DialogFileFilter
  * no filter was selected or if the platform or method doesn't support
  * fetching the selected filter.
  *
+ * In Android, the `filelist` are `content://` URIs. They should be opened
+ * using SDL_IOFromFile() with appropriate modes. This applies both to open
+ * and save file dialog.
+ *
  * \param userdata an app-provided pointer, for the callback's use.
  * \param filelist the file(s) chosen by the user.
  * \param filter index of the selected filter.