fixed another compilation failure

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@15678 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/scm/SubversionChangeLogBuilder.java

@@ -25,6 +25,7 @@ package hudson.scm;
 
 import hudson.model.AbstractBuild;
 import hudson.model.BuildListener;
+import hudson.model.Hudson;
 import hudson.scm.SubversionSCM.ModuleLocation;
 import hudson.FilePath;
 import hudson.util.IOException2;
@@ -117,7 +118,7 @@ public final class SubversionChangeLogBuilder {
     }
 
     private ISVNAuthenticationProvider createAuthenticationProvider() {
-        return SubversionSCM.DescriptorImpl.DESCRIPTOR.createAuthenticationProvider();
+        return Hudson.getInstance().getDescriptorByType(SubversionSCM.DescriptorImpl.class).createAuthenticationProvider();
     }
 
     private boolean buildModule(String url, SVNLogClient svnlc, SVNXMLLogHandler logHandler) throws IOException2 {