gio: fix error handling in async case of GProxyAddressEnumerator
gio: fix error handling in async case of GProxyAddressEnumerator

In the async case, a failed DNS lookup was causing the proxy
resolution to bail out immediately, rather than just moving on to the
next potential proxy (which might not need us to do the DNS lookup
beforehand). Fix that.

Distrotech/glib,johne53/MB3Glib,cosimoc/glib,cention-sany/glib,Distrotech/glib,johne53/MB3Glib,krichter722/glib,cosimoc/glib,cention-sany/glib,mzabaluev/glib,djdeath/glib,MathieuDuponchelle/glib,johne53/MB3Glib,krichter722/glib,endlessm/glib,gale320/glib,Distrotech/glib,endlessm/glib,ieei/glib,gale320/glib,cosimoc/glib,johne53/MB3Glib,gale320/glib,tamaskenez/glib,MathieuDuponchelle/glib,MathieuDuponchelle/glib,mzabaluev/glib,cention-sany/glib,gale320/glib,lukasz-skalski/glib,endlessm/glib,Distrotech/glib,krichter722/glib,lukasz-skalski/glib,krichter722/glib,djdeath/glib,tchakabam/glib,tchakabam/glib,tamaskenez/glib,cosimoc/glib,ieei/glib,tamaskenez/glib,tchakabam/glib,cosimoc/glib,MathieuDuponchelle/glib,MathieuDuponchelle/glib,lukasz-skalski/glib,cention-sany/glib,krichter722/glib,tchakabam/glib,lukasz-skalski/glib,djdeath/glib,cention-sany/glib,mzabaluev/glib,gale320/glib,tamaskenez/glib,djdeath/glib,ieei/glib,endlessm/glib,johne53/MB3Glib,mzabaluev/glib,ieei/glib,johne53/MB3Glib,tchakabam/glib,Distrotech/glib,lukasz-skalski/glib,mzabaluev/glib,tamaskenez/glib,djdeath/glib,ieei/glib,endlessm/glib