FELIX-4119 Allow customization of DependencyHandler created Callbacks

* Re-applied, it has been forgotten in Clement's big patch

git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@1492157 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/ipojo/runtime/core/src/main/java/org/apache/felix/ipojo/handlers/dependency/DependencyHandler.java b/ipojo/runtime/core/src/main/java/org/apache/felix/ipojo/handlers/dependency/DependencyHandler.java
index 6d66880..90a2e8f 100644
--- a/ipojo/runtime/core/src/main/java/org/apache/felix/ipojo/handlers/dependency/DependencyHandler.java
+++ b/ipojo/runtime/core/src/main/java/org/apache/felix/ipojo/handlers/dependency/DependencyHandler.java
@@ -581,11 +581,14 @@
                 methodType = DependencyCallback.MODIFIED;
             }
 
-            DependencyCallback callback = new DependencyCallback(dep, method, methodType);
-            dep.addDependencyCallback(callback);
+            dep.addDependencyCallback(createDependencyHandler(dep, method, methodType));
         }
     }
 
+    protected DependencyCallback createDependencyHandler(final Dependency dep, final String method, final int type) {
+        return new DependencyCallback(dep, method, type);
+    }
+
     private Filter createAndCheckFilter(String filter) throws ConfigurationException {
         Filter fil = null;
         if (filter != null) {