Fix integration tests.

Author: nmalevanec

lib/internal/Magento/Framework/View/Layout/etc/elements.xsd

@@ -14,7 +14,13 @@
                     <xs:sequence>
                         <xs:element name="updater" type="updaterType" minOccurs="0" maxOccurs="1"/>
                     </xs:sequence>
-                    <xs:attribute name="shared" type="xs:boolean" default="true" use="optional"/>
+                </xs:extension>
+            </xs:complexContent>
+        </xs:complexType>
+        <xs:complexType name="object">
+            <xs:complexContent>
+                <xs:extension base="argumentType">
+                    <xs:attribute name="shared" use="optional" type="xs:boolean"/>
                 </xs:extension>
             </xs:complexContent>
         </xs:complexType>