removed redundant atomic var

consumer/src/main/java/com/flipkart/varadhi/consumer/GroupedMessageSrc.java

@@ -59,8 +59,6 @@ public class GroupedMessageSrc<O extends Offset> implements MessageSrc {
  */
  private final AtomicReference<NextMsgsRequest> pendingRequest = new AtomicReference<>();
 
- private final AtomicBoolean pendingRequestWaitingOnFreeGroups = new AtomicBoolean(false);
-
  /**
  * Attempt to fill the message array with one message from each group.
  * Subsequent messages from a group are not fetched until the previous message is consumed.
@@ -81,7 +79,6 @@ public CompletableFuture<Integer> nextMessages(MessageTracker[] messages) {
  throw new IllegalStateException(
  "nextMessages method is not supposed to be called concurrently. There seems to be a pending nextMessage call");
  }
- pendingRequestWaitingOnFreeGroups.set(true);
 
  // incomplete result is saved. trigger new message fetch.
  optionallyFetchNewMessages();
@@ -95,9 +92,8 @@ public CompletableFuture<Integer> nextMessages(MessageTracker[] messages) {
  }
 
  private void tryCompletePendingRequest() {
- if (pendingRequestWaitingOnFreeGroups.compareAndSet(true, false)) {
- // ohh, a free group was there and I am able to grab the request for completion.
- NextMsgsRequest request = pendingRequest.getAndSet(null);
+ NextMsgsRequest request;
+ if ((request = pendingRequest.getAndSet(null)) != null) {
  request.result.complete(nextMessagesInternal(request.messages));
  }
  }