Revert "fix: Set x-goog-request-params for streaming pull request"

This reverts commit 3185a3e.

google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/v1/StreamingSubscriberConnection.java

@@ -36,8 +36,6 @@
 import com.google.api.gax.rpc.StreamController;
 import com.google.cloud.pubsub.v1.MessageDispatcher.AckProcessor;
 import com.google.cloud.pubsub.v1.stub.SubscriberStub;
-import com.google.common.collect.ImmutableList;
-import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Lists;
 import com.google.common.util.concurrent.MoreExecutors;
 import com.google.protobuf.Any;
@@ -88,8 +86,6 @@ final class StreamingSubscriberConnection extends AbstractApiService implements
 
   private Duration inititalStreamAckDeadline;
 
-  private final Map<String, List<String>> streamMetadata;
-
   private final SubscriberStub subscriberStub;
   private final int channelAffinity;
   private final String subscription;
@@ -138,9 +134,6 @@ private StreamingSubscriberConnection(Builder builder) {
       inititalStreamAckDeadline = builder.maxDurationPerAckExtension;
     }
 
-    streamMetadata =
-        ImmutableMap.of("x-goog-request-params", ImmutableList.of("subscription=" + subscription));
-
     subscriberStub = builder.subscriberStub;
     channelAffinity = builder.channelAffinity;
 
@@ -280,9 +273,7 @@ private void initialize() {
             .streamingPullCallable()
             .splitCall(
                 responseObserver,
-                GrpcCallContext.createDefault()
-                    .withChannelAffinity(channelAffinity)
-                    .withExtraHeaders(streamMetadata));
+                GrpcCallContext.createDefault().withChannelAffinity(channelAffinity));
 
     logger.log(Level.FINER, "Initializing stream to subscription {0}", subscription);
     // We need to set streaming ack deadline, but it's not useful since we'll modack to send receipt