Fix #5473 - Extra shadow on share sheet background view (#5532)
Fix #5473 - Extra shadow on share sheet background view (#5532)

* Fix #5473 - Extra shadow on share sheet background view

* Keep iOS 12 behaviour

Bunn/firefox-ios,Bunn/firefox-ios,mozilla-mobile/firefox-ios,Acidburn0zzz/firefox-ios,garvankeeley/firefox-ios,Acidburn0zzz/firefox-ios,Acidburn0zzz/firefox-ios,mkaply/firefox-ios,mozilla-mobile/firefox-ios,garvankeeley/firefox-ios,st3fan/firefox-ios,AaronMT/firefox-ios,st3fan/firefox-ios,flodolo/firefox-ios,garvankeeley/firefox-ios,garvankeeley/firefox-ios,AaronMT/firefox-ios,StYaphet/firefox-ios,Acidburn0zzz/firefox-ios,StYaphet/firefox-ios,st3fan/firefox-ios,AaronMT/firefox-ios,AaronMT/firefox-ios,flodolo/firefox-ios,mkaply/firefox-ios,Acidburn0zzz/firefox-ios,st3fan/firefox-ios,mozilla-mobile/firefox-ios,AaronMT/firefox-ios,AaronMT/firefox-ios,flodolo/firefox-ios,mkaply/firefox-ios,Bunn/firefox-ios,st3fan/firefox-ios,mkaply/firefox-ios,AaronMT/firefox-ios,StYaphet/firefox-ios,flodolo/firefox-ios,Bunn/firefox-ios,garvankeeley/firefox-ios,mozilla-mobile/firefox-ios,mozilla-mobile/firefox-ios,StYaphet/firefox-ios,mkaply/firefox-ios,garvankeeley/firefox-ios,Acidburn0zzz/firefox-ios,Acidburn0zzz/firefox-ios,st3fan/firefox-ios,flodolo/firefox-ios,flodolo/firefox-ios,Bunn/firefox-ios,mkaply/firefox-ios,st3fan/firefox-ios,st3fan/firefox-ios,StYaphet/firefox-ios,Acidburn0zzz/firefox-ios,Bunn/firefox-ios,StYaphet/firefox-ios,mkaply/firefox-ios,Bunn/firefox-ios,garvankeeley/firefox-ios,flodolo/firefox-ios,mozilla-mobile/firefox-ios,mozilla-mobile/firefox-ios,StYaphet/firefox-ios,StYaphet/firefox-ios