Adds soft-reboot support to libvirt

* Falls back to hard reboot if guest doesn't respond
 * Cleans up reboot/rescue/unrescue interaction
 * Fixed fake for tests
 * Added a force hard reboot test to verify fallback works
 * Fixes bug 939557

Change-Id: I8d0c9a35725de5e5bfb8f13a2d869c6122ba44ef

nova/tests/fakelibvirt.py

@@ -288,8 +288,12 @@ class Domain(object):
     def suspend(self):
         self._state = VIR_DOMAIN_PAUSED
 
+    def shutdown(self):
+        self._state = VIR_DOMAIN_SHUTDOWN
+        self._connection._mark_not_running(self)
+
     def info(self):
-        return [VIR_DOMAIN_RUNNING,
+        return [self._state,
                 long(self._def['memory']),
                 long(self._def['memory']),
                 self._def['vcpu'],

nova/tests/test_virt_drivers.py

@@ -476,6 +476,10 @@ class LibvirtConnTestCase(_VirtDriverTestCase):
             nova.virt.libvirt.firewall.libvirt = self.saved_libvirt
         super(LibvirtConnTestCase, self).tearDown()
 
+    def test_force_hard_reboot(self):
+        self.flags(libvirt_wait_soft_reboot_seconds=0)
+        self.test_reboot()
+
     @test.skip_test("Test nothing, but this method "
                     "needed to override superclass.")
     def test_migrate_disk_and_power_off(self):