o Revised error handling, API misuse is really not a model/network problem

git-svn-id: https://svn.apache.org/repos/asf/maven/components/trunk@795622 13f79535-47bb-0310-9956-ffa450edef68

maven-model-builder/src/main/java/org/apache/maven/model/building/DefaultModelBuilder.java

@@ -488,10 +488,8 @@ public class DefaultModelBuilder
 
         if ( modelResolver == null )
         {
-            problems.add( new ModelProblem( "Non-resolvable parent POM " + toId( parent ) + " for POM "
-                + toSourceHint( childModel ) + ": " + "No model resolver provided", ModelProblem.Severity.FATAL,
-                                            toSourceHint( childModel ) ) );
-            throw new ModelBuildingException( problems );
+            throw new IllegalArgumentException( "no model resolver provided, cannot resolve parent POM "
+                + toId( parent ) + " for POM " + toSourceHint( childModel ) );
         }
 
         ModelSource modelSource;