Http2ClientStream overwrites error message
[Http2ClientStream.transportHeadersReceived()](https://github.com/grpc/grpc-java/blob/d0aad72441f2f110910003599bb923db6f671f02/core/src/main/java/io/grpc/transport/Http2ClientStream.java#L102) is calling withDescription instead of augmentDescription. This hinders debugging what went wrong.

@yang-g, since he is interested in when this is resolved.

diff --git a/core/src/main/java/io/grpc/transport/Http2ClientStream.java b/core/src/main/java/io/grpc/transport/Http2ClientStream.java
index badc7c0f2..85577cc8f 100644
--- a/core/src/main/java/io/grpc/transport/Http2ClientStream.java
+++ b/core/src/main/java/io/grpc/transport/Http2ClientStream.java
@@ -99,7 +99,7 @@ public abstract class Http2ClientStream extends AbstractClientStream<Integer> {
     if (transportError != null) {
       // Note we don't immediately report the transport error, instead we wait for more data on the
       // stream so we can accumulate more detail into the error before reporting it.
-      transportError = transportError.withDescription("\\n" + headers.toString());
+      transportError = transportError.augmentDescription("\\n" + headers.toString());
       errorCharset = extractCharset(headers);
     } else {
       stripTransportDetails(headers);
['core/src/main/java/io/grpc/transport/Http2ClientStream.java']