[198744] NPE in EditModelRegistry
diff --git a/plugins/org.eclipse.wst.common.emfworkbench.integration/src/org/eclipse/wst/common/internal/emfworkbench/edit/EditModelRegistry.java b/plugins/org.eclipse.wst.common.emfworkbench.integration/src/org/eclipse/wst/common/internal/emfworkbench/edit/EditModelRegistry.java
index 0733b32..dcfa367 100644
--- a/plugins/org.eclipse.wst.common.emfworkbench.integration/src/org/eclipse/wst/common/internal/emfworkbench/edit/EditModelRegistry.java
+++ b/plugins/org.eclipse.wst.common.emfworkbench.integration/src/org/eclipse/wst/common/internal/emfworkbench/edit/EditModelRegistry.java
@@ -304,7 +304,7 @@
 			return this.factory;
 		}
 
-		private void initializeResources() {
+		private synchronized void initializeResources() {
 
 			if (editModelResources == null) {
 				if (configurationElement != null) {
@@ -328,6 +328,7 @@
 					discardConfigurationElementIfNecessary();
 				} else {
 					editModelResources = Collections.EMPTY_LIST;
+					editModelExtensions = Collections.EMPTY_LIST;
 				}
 			}
 		}