node: fix secondary haproxy app fqdn

The secondary HAproxy gear in a HA application should be accessible at
the node httpd proxy via the app fqdn. Previously this extra route was
added as a sort of additional unofficial fqdn for the gear frontend that
resulted in some inconsistencies. This change updates the method used
such that the app fqdn is added as an alias on the gear frontend instead.

Bug 1155677 - HA apps add fqdn entries in frontend http configuration
causing oo-accept-node to FAIL
https://bugzilla.redhat.com/show_bug.cgi?id=1155677

node/lib/openshift-origin-node/model/v2_cart_model.rb

@@ -1061,7 +1061,6 @@ def disconnect_frontend_for_endpoint(cartridge, endpoint)
       # This is only called when a cartridge is removed from a cartridge not a gear delete
       def disconnect_frontend(cartridge)
         gear_env       = ::OpenShift::Runtime::Utils::Environ.for_gear(@container.container_dir)
-        app_dns        = gear_env["OPENSHIFT_APP_DNS"].to_s.downcase
 
         mappings = []
         cartridge.endpoints.each do |endpoint|
@@ -1074,15 +1073,6 @@ def disconnect_frontend(cartridge)
         unless mappings.empty?
           fe_server =  FrontendHttpServer.new(@container)
           fe_server.disconnect(*mappings)
-          if cartridge.web_proxy?
-            gear_fqdn = fe_server.fqdn
-            if gear_fqdn != app_dns
-              # secondary web-proxy gear
-              fe_server.set_fqdn(app_dns)
-              fe_server.disconnect(*mappings)
-              fe_server.set_fqdn(gear_fqdn)
-            end
-          end
         end
       end
 
@@ -1127,17 +1117,9 @@ def connect_frontend(cartridge, rebuild=false)
               logger.info("Connecting frontend mapping for #{@container.uuid}/#{cartridge.name}: "\
                       "[#{mapping.frontend}] => [#{backend_uri}] with options: #{mapping.options}")
               reported_urls = frontend.connect(mapping.frontend, backend_uri, options)
-              if cartridge.web_proxy?
-                gear_fqdn = frontend.fqdn
-                if gear_fqdn != app_dns
-                  # secondary web-proxy gear
-                  frontend.set_fqdn(app_dns)
-                  new_options = options.dup
-                  # target_update will misfire because fqdn has changed
-                  new_options.delete("target_update")
-                  reported_urls += frontend.connect(mapping.frontend, backend_uri, new_options)
-                  frontend.set_fqdn(gear_fqdn)
-                end
+              if cartridge.web_proxy? && frontend.fqdn != app_dns
+                # secondary web-proxy gear should have app DNS routed too
+                frontend.add_alias(app_dns)
               end
               if reported_urls
                 reported_urls.each do |url|