Auto-adjust IPD as in InlineArea. Info may not be available in LM during addAreas().

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/branches/inlineblock@231060 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/fop/area/inline/InlineBlockParent.java

     public void addChildArea(Area childArea) {
         if (childArea instanceof Block && child == null) {
             child = (Block) childArea;
+            increaseIPD(childArea.getAllocIPD());
         } else {
             // TODO: log error, raise exception?
         }