[VOL-5291] - On demand PON & NNI stats

Change-Id: I1950394b08b0a76968b7e68bffd310714c24a3f3
Signed-off-by: Akash Reddy Kankanala <akash.kankanala@radisys.com>
diff --git a/vendor/golang.org/x/net/http2/pipe.go b/vendor/golang.org/x/net/http2/pipe.go
index 684d984..3b9f06b 100644
--- a/vendor/golang.org/x/net/http2/pipe.go
+++ b/vendor/golang.org/x/net/http2/pipe.go
@@ -77,7 +77,10 @@
 	}
 }
 
-var errClosedPipeWrite = errors.New("write on closed buffer")
+var (
+	errClosedPipeWrite        = errors.New("write on closed buffer")
+	errUninitializedPipeWrite = errors.New("write on uninitialized buffer")
+)
 
 // Write copies bytes from p into the buffer and wakes a reader.
 // It is an error to write more data than the buffer can hold.
@@ -91,6 +94,12 @@
 	if p.err != nil || p.breakErr != nil {
 		return 0, errClosedPipeWrite
 	}
+	// pipe.setBuffer is never invoked, leaving the buffer uninitialized.
+	// We shouldn't try to write to an uninitialized pipe,
+	// but returning an error is better than panicking.
+	if p.b == nil {
+		return 0, errUninitializedPipeWrite
+	}
 	return p.b.Write(d)
 }