[grid] One call less when interacting with the queue

Author: diemol

java/server/src/org/openqa/selenium/grid/distributor/local/LocalDistributor.java

@@ -547,10 +547,11 @@ public class NewSessionRunnable implements Runnable {
 
     @Override
     public void run() {
+      List<SessionRequestCapability> queueContents = sessionQueue.getQueueContents();
       if (rejectUnsupportedCaps) {
-        checkMatchingSlot(sessionQueue.getQueueContents());
+        checkMatchingSlot(queueContents);
       }
-      int initialSize = sessionQueue.getQueueContents().size();
+      int initialSize = queueContents.size();
       boolean retry = initialSize != 0;
 
       while (retry) {