[gnome-boxes/wip/feborges/rdp] wizard: Notify when unable to add RDP server

[Felipe Borges <felipeborges src gnome org>]

commit 910a888faab9def1871053bd018a76d045dc3961
Author: Felipe Borges <felipeborges gnome org>
Date:   Wed May 2 15:48:42 2018 +0200

    wizard: Notify when unable to add RDP server
    
    Whenever Boxes is compiled without RDP support (rdp=false build
    option) and the user wants to add an rdp:// address, we present
    an human-readable error message notifying that.
    
    This is a counter measure because we want to advertise the RDP
    support in the "Enter an URL" dialog, but the RDP support is
    optional (build option).

 data/ui/wizard-source.ui | 2 +-
 src/wizard.vala          | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)
---
diff --git a/data/ui/wizard-source.ui b/data/ui/wizard-source.ui
index b59fccfc..4167c602 100644
--- a/data/ui/wizard-source.ui
+++ b/data/ui/wizard-source.ui
@@ -348,7 +348,7 @@
                 <property name="max-width-chars">64</property>
                 <property name="halign">start</property>
                 <property name="xalign">0.0</property>
-                <property name="label" translatable="yes">Enter an address for the box you want to add. 
Addresses can be of installation images, SPICE and VNC servers, or oVirt or Libvirt brokers.</property>
+                <property name="label" translatable="yes">Enter an address for the box you want to add. 
Addresses can be of installation images, SPICE, RDP and VNC servers, or oVirt or Libvirt brokers.</property>
               </object>
               <packing>
                 <property name="expand">True</property>
diff --git a/src/wizard.vala b/src/wizard.vala
index 0b83f95f..cb584b8a 100644
--- a/src/wizard.vala
+++ b/src/wizard.vala
@@ -363,9 +363,10 @@ private void prepare_for_uri (string uri_as_text, string? filename = null) throw
             source.source_type = "spice";
         } else if (uri.scheme == "vnc") {
             // accept any vnc:// uri
-        #if HAVE_RDP
         } else if (uri.scheme == "rdp") {
             // accept any rdp:// uri
+        #if !HAVE_RDP
+          throw new Boxes.Error.INVALID (_("Boxes was compiled without RDP support"));
         #endif
         } else if (uri.scheme.has_prefix ("qemu")) {
             // accept any qemu..:// uri