Bug 578053 - Gnome proxy support does not work with default gsettings

Fixes some problems with proxy configuration from gsettings:

* Avoid querying deprecated/unused keys:
    org.gnome.system.proxy/use-same-proxy
    org.gnome.system.proxy.http/enabled
* Honour enablement of all proxy types by always checking the presence
  of host name and valid port number
* Avoid populating manual "no proxy" list when the system proxy mode is
  not set to manual

Signed-off-by: Mat Booth <mat.booth@gmail.com>
Change-Id: Iccb7ad5f04b27479e97028e50541479ee97dfe9f
Reviewed-on: https://git.eclipse.org/r/c/platform/eclipse.platform.team/+/189301
Tested-by: Platform Bot <platform-bot@eclipse.org>
Reviewed-by: Jeff Johnston <jjohnstn@redhat.com>
Reviewed-by: Alexander Kurtakov <akurtako@redhat.com>
3 files changed