FELIX-1629 : SCR Annotations with Constanst reference may cause NPE. Apply patch from Stefan Seifert

git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@818374 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/scrplugin/src/main/java/org/apache/felix/scrplugin/tags/annotation/defaulttag/Util.java b/scrplugin/src/main/java/org/apache/felix/scrplugin/tags/annotation/defaulttag/Util.java
index a76ac6c..28f71c7 100644
--- a/scrplugin/src/main/java/org/apache/felix/scrplugin/tags/annotation/defaulttag/Util.java
+++ b/scrplugin/src/main/java/org/apache/felix/scrplugin/tags/annotation/defaulttag/Util.java
@@ -347,6 +347,14 @@
     {
         if ( av instanceof AnnotationFieldRef )
         {
+            // during prescan of AnnotationTagProviderManager#hasScrPluginAnnotation this method is called without desc attribute
+            // avoid NPE in this case and just skip value resolving
+            // FELIX-1629
+            if ( desc == null)
+            {
+                return null;
+            }
+
             // getField throws AIOOBE
             // return ((AnnotationFieldRef)av).getField().getInitializationExpression();
             final String s = av.getParameterValue().toString().trim();