166852 Update Configurator reconciles platform.xml with newer features even for sites that have USER-INCLUDE Policy and have explicit inclusion plugin lists.
diff --git a/update/org.eclipse.update.configurator/src/org/eclipse/update/internal/configurator/PlatformConfiguration.java b/update/org.eclipse.update.configurator/src/org/eclipse/update/internal/configurator/PlatformConfiguration.java
index d6ea937..68e6aca 100644
--- a/update/org.eclipse.update.configurator/src/org/eclipse/update/internal/configurator/PlatformConfiguration.java
+++ b/update/org.eclipse.update.configurator/src/org/eclipse/update/internal/configurator/PlatformConfiguration.java
@@ -1218,9 +1218,11 @@
 		long lastChange = config.getDate().getTime();
 		SiteEntry[] sites = config.getSites();
 		for (int s=0; s<sites.length; s++) {
-			long siteTimestamp = sites[s].getChangeStamp();
-			if (siteTimestamp > lastChange)
-				sites[s].loadFromDisk(lastChange);
+			if (sites[s].isUpdateable()) {
+				long siteTimestamp = sites[s].getChangeStamp();
+				if (siteTimestamp > lastChange)
+					sites[s].loadFromDisk(lastChange);
+			}
 		}
 		config.setDirty(true);
 	}