Use correct state classes for Vertical and HorizontalLayout

Change-Id: Ifa52a2ff7225076129de9b0f964b82704221dccd

server/src/com/vaadin/ui/HorizontalLayout.java

@@ -15,6 +15,8 @@
  */
 package com.vaadin.ui;
 
+import com.vaadin.shared.ui.orderedlayout.HorizontalLayoutState;
+
 /**
  * Horizontal layout
  * 
@@ -48,4 +50,9 @@ public class HorizontalLayout extends AbstractOrderedLayout {
         addComponents(children);
     }
 
+    @Override
+    protected HorizontalLayoutState getState() {
+        return (HorizontalLayoutState) super.getState();
+    }
+
 }

server/src/com/vaadin/ui/VerticalLayout.java

@@ -15,6 +15,8 @@
  */
 package com.vaadin.ui;
 
+import com.vaadin.shared.ui.orderedlayout.VerticalLayoutState;
+
 /**
  * Vertical layout
  * 
@@ -48,4 +50,9 @@ public class VerticalLayout extends AbstractOrderedLayout {
         this();
         addComponents(children);
     }
+
+    @Override
+    protected VerticalLayoutState getState() {
+        return (VerticalLayoutState) super.getState();
+    }
 }