Fix virtual navigation page results (JSF2 regression)

Caused by: javax.el.ELException: /incl/documents_layout_table.xhtml @39,35 test="#{documents != null}": /incl/content_view.xhtml @215,82 value="#{provider.currentSelectPage}": Error reading 'currentSelectPage' on type org.nuxeo.ecm.platform.query.nxql.CoreQueryDocumentPageProvider
	at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:114)
	at com.sun.faces.facelets.tag.TagAttributeImpl.getObject(TagAttributeImpl.java:356)
	... 139 more
Caused by: javax.el.ELException: /incl/content_view.xhtml @215,82 value="#{provider.currentSelectPage}": Error reading 'currentSelectPage' on type org.nuxeo.ecm.platform.query.nxql.CoreQueryDocumentPageProvider
	at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:114)
	at org.jboss.el.parser.AstIdentifier.getValue(AstIdentifier.java:40)
	at org.jboss.el.parser.AstNotEqual.getValue(AstNotEqual.java:21)
	at org.jboss.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
	at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109)
	... 140 more
Caused by: javax.el.ELException: Error reading 'currentSelectPage' on type org.nuxeo.ecm.platform.query.nxql.CoreQueryDocumentPageProvider
	at javax.el.BeanELResolver.getValue(BeanELResolver.java:98)
	at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176)
	at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203)
	at org.jboss.el.parser.AstPropertySuffix.getValue(AstPropertySuffix.java:53)
	at org.jboss.el.parser.AstValue.getValue(AstValue.java:67)
	at org.jboss.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
	at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109)
	... 144 more
Caused by: org.nuxeo.ecm.core.api.ClientRuntimeException: cannot find core session
	at org.nuxeo.ecm.platform.query.nxql.CoreQueryDocumentPageProvider.getCoreSession(CoreQueryDocumentPageProvider.java:294)
	at org.nuxeo.ecm.platform.query.nxql.CoreQueryDocumentPageProvider.getCurrentPage(CoreQueryDocumentPageProvider.java:112)
	at org.nuxeo.ecm.platform.query.api.AbstractPageProvider.getCurrentSelectPage(AbstractPageProvider.java:641)
	at org.nuxeo.ecm.platform.query.nxql.CoreQueryDocumentPageProvider.getCurrentSelectPage(CoreQueryDocumentPageProvider.java:357)
	at sun.reflect.GeneratedMethodAccessor245.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:606)
	at javax.el.BeanELResolver.getValue(BeanELResolver.java:87)
	... 150 more