Allow Media Browser view displays to have custom machine names

I have a couple of extra media browser view displays, which I add via hook_views_default_views_alter(). I do not overwrite the entire view.

Unfortunately, it appears that giving a view display a custom machine name results in the display not appearing in the browser popup. The displays must have machine names like "media_browser_N", where N must be a sequential integer.

This makes the use of views via hook_views_default_views_alter() problematic, due to potential collisions with other modules wishing to add displays.