[VOL-4291] Rw-core updates for gRPC migration

Change-Id: I8d5a554409115b29318089671ca4e1ab3fa98810
diff --git a/vendor/go.uber.org/zap/buffer/buffer.go b/vendor/go.uber.org/zap/buffer/buffer.go
index 7592e8c..9e929cd 100644
--- a/vendor/go.uber.org/zap/buffer/buffer.go
+++ b/vendor/go.uber.org/zap/buffer/buffer.go
@@ -23,7 +23,10 @@
 // package's zero-allocation formatters.
 package buffer // import "go.uber.org/zap/buffer"
 
-import "strconv"
+import (
+	"strconv"
+	"time"
+)
 
 const _size = 1024 // by default, create 1 KiB buffers
 
@@ -49,6 +52,11 @@
 	b.bs = strconv.AppendInt(b.bs, i, 10)
 }
 
+// AppendTime appends the time formatted using the specified layout.
+func (b *Buffer) AppendTime(t time.Time, layout string) {
+	b.bs = t.AppendFormat(b.bs, layout)
+}
+
 // AppendUint appends an unsigned integer to the underlying buffer (assuming
 // base 10).
 func (b *Buffer) AppendUint(i uint64) {
@@ -98,6 +106,24 @@
 	return len(bs), nil
 }
 
+// WriteByte writes a single byte to the Buffer.
+//
+// Error returned is always nil, function signature is compatible
+// with bytes.Buffer and bufio.Writer
+func (b *Buffer) WriteByte(v byte) error {
+	b.AppendByte(v)
+	return nil
+}
+
+// WriteString writes a string to the Buffer.
+//
+// Error returned is always nil, function signature is compatible
+// with bytes.Buffer and bufio.Writer
+func (b *Buffer) WriteString(s string) (int, error) {
+	b.AppendString(s)
+	return len(s), nil
+}
+
 // TrimNewline trims any final "\n" byte from the end of the buffer.
 func (b *Buffer) TrimNewline() {
 	if i := len(b.bs) - 1; i >= 0 {