diff -r 000000000000 -r 6474c204b198 mobile/android/base/sync/delegates/NodeAssignmentCallback.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mobile/android/base/sync/delegates/NodeAssignmentCallback.java	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,42 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.sync.delegates;
+
+import java.net.URI;
+
+import org.mozilla.gecko.sync.GlobalSession;
+
+public interface NodeAssignmentCallback {
+  /**
+   * If true, request node assignment from the server, i.e., fetch node/weave cluster URL.
+   */
+  public boolean wantNodeAssignment();
+
+  /**
+   * Called when a new node is assigned. If there already was an old node, the
+   * new node is different from the old node assignment, indicating node
+   * reassignment. If there wasn't an old node, we've been freshly assigned.
+   *
+   * @param globalSession
+   * @param oldClusterURL
+   *          The old node/weave cluster URL (possibly null).
+   * @param newClusterURL
+   *          The new node/weave cluster URL (not null).
+   */
+  public void informNodeAssigned(GlobalSession globalSession, URI oldClusterURL, URI newClusterURL);
+
+  /**
+   * Called when wantNodeAssignment() is true, and the new node assignment is
+   * the same as the old node assignment, indicating a user authentication
+   * error.
+   *
+   * @param globalSession
+   * @param failedClusterURL
+   *          The new node/weave cluster URL.
+   */
+  public void informNodeAuthenticationFailed(GlobalSession globalSession, URI failedClusterURL);
+
+  public String nodeWeaveURL();
+}