monitoring: Rearrange code in the HostdowntimestarthistoryQuery

refs #9956

modules/monitoring/library/Monitoring/Backend/Ido/Query/HostdowntimestarthistoryQuery.php

@@ -27,9 +27,6 @@ class HostdowntimestarthistoryQuery extends IdoQuery
      * {@inheritdoc}
      */
     protected $columnMap = array(
-        'instances' => array(
-            'instance_name' => 'i.instance_name'
-        ),
         'downtimehistory' => array(
             'host'          => 'ho.name1 COLLATE latin1_general_ci',
             'host_name'     => 'ho.name1',
@@ -49,6 +46,9 @@ class HostdowntimestarthistoryQuery extends IdoQuery
             'host_alias'        => 'h.alias',
             'host_display_name' => 'h.display_name COLLATE latin1_general_ci'
         ),
+        'instances' => array(
+            'instance_name' => 'i.instance_name'
+        ),
         'servicegroups' => array(
             'servicegroup'          => 'sgo.name1 COLLATE latin1_general_ci',
             'servicegroup_name'     => 'sgo.name1',
@@ -132,6 +132,18 @@ class HostdowntimestarthistoryQuery extends IdoQuery
         );
     }
 
+    /**
+     * Join instances
+     */
+    protected function joinInstances()
+    {
+        $this->select->join(
+            array('i' => $this->prefix . 'instances'),
+            'i.instance_id = hdh.instance_id',
+            array()
+        );
+    }
+
     /**
      * Join service groups
      */
@@ -168,16 +180,4 @@ class HostdowntimestarthistoryQuery extends IdoQuery
             array()
         );
     }
-
-    /**
-     * Join instances
-     */
-    protected function joinInstances()
-    {
-        $this->select->join(
-            array('i' => $this->prefix . 'instances'),
-            'i.instance_id = hdh.instance_id',
-            array()
-        );
-    }
 }