All retrieved events are marked as transparent

[paulvt]

It seems that the Google Calendar API only mentions in event JSON when the event is actually transparent. If the event is opaque, it is not part of the event JSON.
However, then for the opaque events Event.new_from_feed passes nil as value to transparency= (via initialize) which will then default to it setting @transparency to "transparent" which is the wrong outcome.
As a result, all retrieved events are marked as transparent.

A solution would be to have initialize do:

self.transparency = params[:transparency] || "opaque"

Another solution would be to have new_from_feed not parse it as part of the standard list of params but have an explicit line:

params[:transparency] = e['transparency'] || "opaque"

I could not find in the docs whether it transparancy actually should default to "opaque" (the UI does). If this case, maybe event's transparency= could be adapted to use:

if val.nil? || val == false || val.to_s.downcase == 'opaque'