fix(generator): delay removing streaming response until used

google-cloud-speech/src/test/java/com/google/cloud/speech/v1/MockSpeechImpl.java

@@ -90,11 +90,12 @@ public void longRunningRecognize(
   @Override
   public StreamObserver<StreamingRecognizeRequest> streamingRecognize(
       final StreamObserver<StreamingRecognizeResponse> responseObserver) {
-    final Object response = responses.remove();
     StreamObserver<StreamingRecognizeRequest> requestObserver =
         new StreamObserver<StreamingRecognizeRequest>() {
           @Override
           public void onNext(StreamingRecognizeRequest value) {
+            requests.add(value);
+            final Object response = responses.remove();
             if (response instanceof StreamingRecognizeResponse) {
               responseObserver.onNext((StreamingRecognizeResponse) response);
             } else if (response instanceof Exception) {

google-cloud-speech/src/test/java/com/google/cloud/speech/v1p1beta1/MockSpeechImpl.java

@@ -90,11 +90,12 @@ public void longRunningRecognize(
   @Override
   public StreamObserver<StreamingRecognizeRequest> streamingRecognize(
       final StreamObserver<StreamingRecognizeResponse> responseObserver) {
-    final Object response = responses.remove();
     StreamObserver<StreamingRecognizeRequest> requestObserver =
         new StreamObserver<StreamingRecognizeRequest>() {
           @Override
           public void onNext(StreamingRecognizeRequest value) {
+            requests.add(value);
+            final Object response = responses.remove();
             if (response instanceof StreamingRecognizeResponse) {
               responseObserver.onNext((StreamingRecognizeResponse) response);
             } else if (response instanceof Exception) {

synth.metadata

@@ -4,23 +4,23 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-speech.git",
-        "sha": "6dee1350b47734f3dfff19e3f3fa81a1d502253b"
+        "sha": "8fe074c183d0521a4ea645c3c498248b33d7debd"
       }
     },
     {
       "git": {
         "name": "googleapis",
         "remote": "https://github.com/googleapis/googleapis.git",
-        "sha": "4d61e1cb40184a7ad63ef37b1813f6608718674a",
-        "internalRef": "306280989"
+        "sha": "28e76243c23cc282efbb288cb558c174e3e5e9ee",
+        "internalRef": "308294748"
       }
     },
     {
       "git": {
         "name": "googleapis",
         "remote": "https://github.com/googleapis/googleapis.git",
-        "sha": "4d61e1cb40184a7ad63ef37b1813f6608718674a",
-        "internalRef": "306280989"
+        "sha": "28e76243c23cc282efbb288cb558c174e3e5e9ee",
+        "internalRef": "308294748"
       }
     },
     {