Ensure that the core properties are there before saving them, in case they have not yet been lazy-created

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1662971 13f79535-47bb-0310-9956-ffa450edef68

src/ooxml/java/org/apache/poi/openxml4j/opc/ZipPackage.java

@@ -444,6 +444,8 @@ public final class ZipPackage extends Package {
                 this.getPartsByRelationshipType(PackageRelationshipTypes.CORE_PROPERTIES_ECMA376).size() == 0    ) {
 				logger.log(POILogger.DEBUG,"Save core properties part");
 				
+				// Ensure that core properties are added if missing
+				getPackageProperties();
 				// Add core properties to part list ...
 				addPackagePart(this.packageProperties);
 				// ... and to add its relationship ...