Fix some more undefined property warnings

https://bugzilla.gnome.org/show_bug.cgi?id=787907

js/ui/dnd.js

@@ -94,6 +94,7 @@ var _Draggable = new Lang.Class({
             this.disconnectAll();
         }));
         this._onEventId = null;
+        this._touchSequence = null;
 
         this._restoreOnSuccess = params.restoreOnSuccess;
         this._dragActorMaxSize = params.dragActorMaxSize;

js/ui/workspace.js

@@ -1090,6 +1090,7 @@ var Workspace = new Lang.Class({
         // do some simple aspect ratio like math to fit the layout calculated
         // for the full geometry into this area.
         this._actualGeometry = null;
+        this._actualGeometryLater = 0;
 
         this._currentLayout = null;
 

js/ui/workspaceSwitcherPopup.js

@@ -31,6 +31,7 @@ var WorkspaceSwitcherPopup = new Lang.Class({
         this._itemSpacing = 0;
         this._childHeight = 0;
         this._childWidth = 0;
+        this._timeoutId = 0;
         this._list.connect('style-changed', Lang.bind(this, function() {
                                                         this._itemSpacing = this._list.get_theme_node().get_length('spacing');
                                                      }));