Import patches-unapplied version 2.477 to ubuntu/artful-proposed

Imported using git-ubuntu import.

Changelog parent: 95f6bb3dfc

New changelog entries:
  * Fix server live image to pull subiquity from the stable channel, not
    from edge.

debian/changelog

@@ -1,3 +1,10 @@
+livecd-rootfs (2.477) artful; urgency=medium
+
+  * Fix server live image to pull subiquity from the stable channel, not
+    from edge.
+
+ -- Steve Langasek <steve.langasek@ubuntu.com>  Sun, 15 Oct 2017 13:44:56 -0700
+
 livecd-rootfs (2.476) artful; urgency=medium
 
   * snap.subiquity.started.service must be RemainAfterExit=yes to satisfy

live-build/ubuntu-server/hooks/032-installer-squashfs.binary

@@ -50,7 +50,7 @@ chroot $SQUASH_ROOT sh -c '
 set -x;
 cd /var/lib/snapd/seed;
 sudo SNAPPY_STORE_NO_CDN=1 snap download core;
-sudo SNAPPY_STORE_NO_CDN=1 snap download --channel=edge subiquity;
+sudo SNAPPY_STORE_NO_CDN=1 snap download subiquity;
 
 CORE_SNAP=$(ls -1 core*.snap);
 SUBIQUITY_SNAP=$(ls -1 subiquity*.snap);