Make SecureCredentialsFactory public

Access to secure.config is useful to more than just replication plugin.
Allow instantiating this class from packages other than replication
plugin. Specifically this is useful, as this class can be used from
pull-replication too.

Change-Id: Id268c869e993c6cabacfa0043ec269172e0efba1
(cherry picked from commit c09a7c08fb44094c7475313ac52154adac39a54c)
diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/SecureCredentialsFactory.java b/src/main/java/com/googlesource/gerrit/plugins/replication/SecureCredentialsFactory.java
index c518091..e79491c 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/SecureCredentialsFactory.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/SecureCredentialsFactory.java
@@ -24,11 +24,11 @@
 import org.eclipse.jgit.util.FS;
 
 /** Looks up a remote's password in secure.config. */
-class SecureCredentialsFactory implements CredentialsFactory {
+public class SecureCredentialsFactory implements CredentialsFactory {
   private final Config config;
 
   @Inject
-  SecureCredentialsFactory(SitePaths site) throws ConfigInvalidException, IOException {
+  public SecureCredentialsFactory(SitePaths site) throws ConfigInvalidException, IOException {
     config = load(site);
   }