bufio: use max/min func

Change-Id: I39e03e2e00964cf4e3ff7df3c40b995a48040aec

src/bufio/bufio.go

@@ -50,11 +50,8 @@ func NewReaderSize(rd io.Reader, size int) *Reader {
 	if ok && len(b.buf) >= size {
 		return b
 	}
-	if size < minReadBufferSize {
-		size = minReadBufferSize
-	}
 	r := new(Reader)
-	r.reset(make([]byte, size), rd)
+	r.reset(make([]byte, max(size, minReadBufferSize)), rd)
 	return r
 }
 

src/bufio/scan.go

@@ -198,9 +198,7 @@ func (s *Scanner) Scan() bool {
 			if newSize == 0 {
 				newSize = startBufSize
 			}
-			if newSize > s.maxTokenSize {
-				newSize = s.maxTokenSize
-			}
+			newSize = min(newSize, s.maxTokenSize)
 			newBuf := make([]byte, newSize)
 			copy(newBuf, s.buf[s.start:s.end])
 			s.buf = newBuf