Servers should send RST_STREAM(NO_ERROR) after trailers if client is not half-closed

[ejona86]

The HTTP/2 spec calls out this case specifically saying that servers MAY send the RST_STREAM. For gRPC, we are going to consider it more of a SHOULD, although clients still have to assume it is a MAY because intermediaries may in be play.

[ejona86]

@ericgribkoff, was this resolved?

[ericgribkoff]

My changes only applied to the client-side, so I believe this issue remains on the server.

[creamsoup]

filed an issue on netty

[ejona86]

This came up again in #5443.