Bug 513128 - NPE on shutdown after error in start

Change-Id: I4afc85772d16a347f1063a6fbdb5651766f4c051
Signed-off-by: Andrey Loskutov <loskutov@gmx.de>
diff --git a/bundles/org.eclipse.core.resources/src/org/eclipse/core/resources/ResourcesPlugin.java b/bundles/org.eclipse.core.resources/src/org/eclipse/core/resources/ResourcesPlugin.java
index 3e20d95..4bf9570 100644
--- a/bundles/org.eclipse.core.resources/src/org/eclipse/core/resources/ResourcesPlugin.java
+++ b/bundles/org.eclipse.core.resources/src/org/eclipse/core/resources/ResourcesPlugin.java
@@ -481,9 +481,12 @@
 		debugRegistration.unregister();
 		debugRegistration = null;
 
-		if (workspace == null)
+		if (workspace == null) {
 			return;
-		workspaceRegistration.unregister();
+		}
+		if (workspaceRegistration != null) {
+			workspaceRegistration.unregister();
+		}
 		// save the preferences for this plug-in
 		getPlugin().savePluginPreferences();
 		workspace.close(null);