Remove unreachable statement checking for ext-proc stream state already closed when data plane onClose happens. Because the same serializing executor is used for both, and if ext-proc stream closed, the passthrough mode would have been set, this condition can never evaluate to true.

Author: kannanjgithub

xds/src/main/java/io/grpc/xds/ExternalProcessorFilter.java

@@ -1653,8 +1653,8 @@ public void onMessage(InputStream message) {
       @Override
       public void onClose(Status status, Metadata trailers) {
         dataPlaneClientCall.serverTrailersStartNanos = System.nanoTime();
-        ExtProcStreamState state = dataPlaneClientCall.extProcStreamState.get();
-        if (state.isFailed()
+        ExtProcStreamState extProcStreamState = dataPlaneClientCall.extProcStreamState.get();
+        if (extProcStreamState.isFailed()
             && !dataPlaneClientCall.config.getFailureModeAllow()) {
           if (dataPlaneClientCall.markDataPlaneCallClosed()) {
             proceedWithClose(Status.UNAVAILABLE.withDescription("External processor stream failed")
@@ -1672,11 +1672,6 @@ public void onClose(Status status, Metadata trailers) {
         this.savedStatus = status;
         this.savedTrailers = trailers;
 
-        if (state.isCompleted()) {
-          proceedWithClose();
-          return;
-        }
-
         if (savedHeaders != null) {
           return;
         }