xRDP fixes for Hyper-V build

- use of linux-azure, which is the optimized kernel for Hyper-V by
Microsoft
- xRDP configuration changes due to the config changes in this version
compared to 18.04.
- 46-allow-update-repo.pkla inclusion to aviod "Authentication required
to refresh system repositories" bug in xRDP

live-build/ubuntu/hooks/040-hyperv-desktop-images.binary

@@ -40,7 +40,7 @@ trap cleanup_hyperv EXIT
 # Perform customisations
 
 chroot "${scratch_d}" apt-get update -y
-chroot "${scratch_d}" apt-get -y install xrdp linux-tools-virtual linux-cloud-tools-virtual
+chroot "${scratch_d}" apt-get -y install xrdp linux-azure linux-tools-virtual linux-cloud-tools-virtual
 
 cat > ${scratch_d}/etc/modules-load.d/hyperv.conf << EOF
 ${IMAGE_STR}
@@ -55,8 +55,8 @@ EOF
 
 CHANGED_FILE_SUFFIX=.replaced-by-desktop-img-build
 
-# use vsock transport.
-sed -i${CHANGED_FILE_SUFFIX} -e 's/use_vsock=false/use_vsock=true/g' "${scratch_d}/etc/xrdp/xrdp.ini"
+# use vsock transport
+sed -i${CHANGED_FILE_SUFFIX} -e 's/port=3389/port=vsock:\/\/-1:3389/g' "${scratch_d}/etc/xrdp/xrdp.ini"
 # use rdp security.
 sed -i${CHANGED_FILE_SUFFIX} -e 's/security_layer=negotiate/security_layer=rdp/g' "${scratch_d}/etc/xrdp/xrdp.ini"
 # remove encryption validation.
@@ -74,6 +74,9 @@ exec /etc/xrdp/startwm.sh
 EOF
 chmod a+x "${scratch_d}/etc/xrdp/startubuntu.sh"
 
+# set to use the system Window manager
+sed -i${CHANGED_FILE_SUFFIX} -e 's/EnableUserWindowManager=true/EnableUserWindowManager=0/g' "${scratch_d}/etc/xrdp/sesman.ini"
+
 # use the script to setup the ubuntu session
 sed -i${CHANGED_FILE_SUFFIX} -e 's/startwm/startubuntu/g' "${scratch_d}/etc/xrdp/sesman.ini"
 
@@ -100,6 +103,15 @@ ResultInactive=no
 ResultActive=yes
 EOF
 
+cat >/etc/polkit-1/localauthority/50-local.d/46-allow-update-repo.pkla <<EOF
+[Allow Package Management all Users]
+Identity=unix-user:*
+Action=org.freedesktop.packagekit.system-sources-refresh
+ResultAny=yes
+ResultInactive=yes
+ResultActive=yes
+EOF
+
 sed -i${CHANGED_FILE_SUFFIX} -e 's|After=|ConditionPathExists=!/var/lib/oem-config/run\nAfter=|g' "${scratch_d}/lib/systemd/system/xrdp.service"
 
 # End xrdp customisation