diff --git a/vendor/google.golang.org/grpc/internal/transport/handler_server.go b/vendor/google.golang.org/grpc/internal/transport/handler_server.go
index 73b41ea..78f9ddc 100644
--- a/vendor/google.golang.org/grpc/internal/transport/handler_server.go
+++ b/vendor/google.golang.org/grpc/internal/transport/handler_server.go
@@ -24,6 +24,7 @@
 package transport
 
 import (
+	"bytes"
 	"context"
 	"errors"
 	"fmt"
@@ -63,9 +64,6 @@
 	if _, ok := w.(http.Flusher); !ok {
 		return nil, errors.New("gRPC requires a ResponseWriter supporting http.Flusher")
 	}
-	if _, ok := w.(http.CloseNotifier); !ok {
-		return nil, errors.New("gRPC requires a ResponseWriter supporting http.CloseNotifier")
-	}
 
 	st := &serverHandlerTransport{
 		rw:             w,
@@ -176,17 +174,11 @@
 
 // do runs fn in the ServeHTTP goroutine.
 func (ht *serverHandlerTransport) do(fn func()) error {
-	// Avoid a panic writing to closed channel. Imperfect but maybe good enough.
 	select {
 	case <-ht.closedCh:
 		return ErrConnClosing
-	default:
-		select {
-		case ht.writes <- fn:
-			return nil
-		case <-ht.closedCh:
-			return ErrConnClosing
-		}
+	case ht.writes <- fn:
+		return nil
 	}
 }
 
@@ -237,7 +229,6 @@
 		if ht.stats != nil {
 			ht.stats.HandleRPC(s.Context(), &stats.OutTrailer{})
 		}
-		close(ht.writes)
 	}
 	ht.Close()
 	return err
@@ -315,19 +306,13 @@
 		ctx, cancel = context.WithCancel(ctx)
 	}
 
-	// requestOver is closed when either the request's context is done
-	// or the status has been written via WriteStatus.
+	// requestOver is closed when the status has been written via WriteStatus.
 	requestOver := make(chan struct{})
-
-	// clientGone receives a single value if peer is gone, either
-	// because the underlying connection is dead or because the
-	// peer sends an http2 RST_STREAM.
-	clientGone := ht.rw.(http.CloseNotifier).CloseNotify()
 	go func() {
 		select {
 		case <-requestOver:
 		case <-ht.closedCh:
-		case <-clientGone:
+		case <-ht.req.Context().Done():
 		}
 		cancel()
 		ht.Close()
@@ -363,7 +348,7 @@
 		ht.stats.HandleRPC(s.ctx, inHeader)
 	}
 	s.trReader = &transportReader{
-		reader:        &recvBufferReader{ctx: s.ctx, ctxDone: s.ctx.Done(), recv: s.buf},
+		reader:        &recvBufferReader{ctx: s.ctx, ctxDone: s.ctx.Done(), recv: s.buf, freeBuffer: func(*bytes.Buffer) {}},
 		windowHandler: func(int) {},
 	}
 
@@ -377,7 +362,7 @@
 		for buf := make([]byte, readSize); ; {
 			n, err := req.Body.Read(buf)
 			if n > 0 {
-				s.buf.put(recvMsg{data: buf[:n:n]})
+				s.buf.put(recvMsg{buffer: bytes.NewBuffer(buf[:n:n])})
 				buf = buf[n:]
 			}
 			if err != nil {
@@ -407,10 +392,7 @@
 func (ht *serverHandlerTransport) runStream() {
 	for {
 		select {
-		case fn, ok := <-ht.writes:
-			if !ok {
-				return
-			}
+		case fn := <-ht.writes:
 			fn()
 		case <-ht.closedCh:
 			return