Make relay arguments consistent.

library/src/org/whispersystems/textsecure/push/PushServiceSocket.java

@@ -139,7 +139,7 @@ public class PushServiceSocket {
      makeRequest(String.format(PREKEY_PATH, ""), "PUT", PreKeyList.toJson(new PreKeyList(lastResortEntity, entities)));
   }
 
-  public PreKeyEntity getPreKey(String number, String relay) throws IOException {
+  public PreKeyEntity getPreKey(String relay, String number) throws IOException {
     String path = String.format(PREKEY_PATH, number);
 
     if (relay != null) {

src/org/thoughtcrime/securesms/transport/PushTransport.java

@@ -191,7 +191,7 @@ public class PushTransport extends BaseTransport {
     IdentityKeyPair      identityKeyPair = IdentityKeyUtil.getIdentityKeyPair(context, masterSecret);
     IdentityKey          identityKey     = identityKeyPair.getPublicKey();
     String               relay           = Directory.getInstance(context).getRelay(canonicalRecipientNumber);
-    PreKeyEntity         preKey          = socket.getPreKey(canonicalRecipientNumber, relay);
+    PreKeyEntity         preKey          = socket.getPreKey(relay, canonicalRecipientNumber);
     KeyExchangeProcessor processor       = new KeyExchangeProcessor(context, masterSecret, recipient);
 
     processor.processKeyExchangeMessage(preKey);