HTTPS proxy is only enabled if the proxied connection is also SSL #210

irb(main):001> require 'net/http'
=> true
irb(main):002> n = Net::HTTP.new('192.0.2.10', 80, '127.0.0.1', 5000, nil, nil, nil, true)
=> #<Net::HTTP 192.0.2.10:80 open=false>
irb(main):003> n.instance_variable_get(:@proxy_use_ssl)
=> true
irb(main):004> n.start
=> #<Net::HTTP 192.0.2.10:80 open=true>
irb(main):005> n.get('/')

GET http://192.0.2.10/ HTTP/1.1
Accept-Encoding: gzip;q=1.0,deflate;q=0.6,identity;q=0.3
Accept: */*
User-Agent: Ruby
Host: 192.0.2.10