Merge lp:~azzar1/unity/fix-991637-6.0 into lp:unity/6.0

[Andrea Azzarone]

Backport fix for 991637.

== Problem ==
unity launcher vanishes when switching to mirrored displays

== Test ==
Unit test added.

[Brandon Schaefer (brandontschaefer)]

LGTM

review: Approve

=== modified file 'launcher/LauncherController.cpp'
--- launcher/LauncherController.cpp	2012-10-18 16:44:39 +0000
+++ launcher/LauncherController.cpp	2013-02-14 20:05:39 +0000
@@ -198,7 +198,7 @@
       launchers[i] = nux::ObjectPtr<Launcher>(CreateLauncher(i));
     }
 
-    int monitor = (num_launchers == 1) ? primary : i;
+    int monitor = (num_launchers == 1 && num_monitors > 1) ? primary : i;
 
     if (launchers[i]->monitor() != monitor)
     {
 
=== modified file 'tests/test_launcher_controller.cpp'
--- tests/test_launcher_controller.cpp	2012-10-17 10:26:44 +0000
+++ tests/test_launcher_controller.cpp	2013-02-14 20:05:39 +0000
@@ -322,6 +322,16 @@
   }
 }
 
+TEST_F(TestLauncherController, MirroredMultimonitorSingleLauncherOnExternalMonitor)
+{
+  // See lp bug 991637
+  lc.multiple_launchers = false;
+  uscreen.SetPrimary(1);
+
+  ASSERT_EQ(lc.launchers().size(), 1);
+  ASSERT_EQ(lc.launcher().monitor(), 0);
+}
+
 TEST_F(TestLauncherController, MultimonitorSwitchToMultipleLaunchers)
 {
   lc.multiple_launchers = false;