Remove pools_nopool.go & build tag from pools.go

Fix #11576

Signed-off-by: Gleb Shepelev <shepelyov.g@gmail.com>

pkg/pools/pools.go

@@ -1,5 +1,3 @@
-// +build go1.3
-
 // Package pools provides a collection of pools which provide various
 // data types with buffers. These can be used to lower the number of
 // memory allocations and reuse buffers.

pkg/pools/pools_nopool.go

@@ -1,73 +0,0 @@
-// +build !go1.3
-
-package pools
-
-import (
-	"bufio"
-	"io"
-
-	"github.com/docker/docker/pkg/ioutils"
-)
-
-var (
-	BufioReader32KPool *BufioReaderPool
-	BufioWriter32KPool *BufioWriterPool
-)
-
-const buffer32K = 32 * 1024
-
-type BufioReaderPool struct {
-	size int
-}
-
-func init() {
-	BufioReader32KPool = newBufioReaderPoolWithSize(buffer32K)
-	BufioWriter32KPool = newBufioWriterPoolWithSize(buffer32K)
-}
-
-func newBufioReaderPoolWithSize(size int) *BufioReaderPool {
-	return &BufioReaderPool{size: size}
-}
-
-func (bufPool *BufioReaderPool) Get(r io.Reader) *bufio.Reader {
-	return bufio.NewReaderSize(r, bufPool.size)
-}
-
-func (bufPool *BufioReaderPool) Put(b *bufio.Reader) {
-	b.Reset(nil)
-}
-
-func (bufPool *BufioReaderPool) NewReadCloserWrapper(buf *bufio.Reader, r io.Reader) io.ReadCloser {
-	return ioutils.NewReadCloserWrapper(r, func() error {
-		if readCloser, ok := r.(io.ReadCloser); ok {
-			return readCloser.Close()
-		}
-		return nil
-	})
-}
-
-type BufioWriterPool struct {
-	size int
-}
-
-func newBufioWriterPoolWithSize(size int) *BufioWriterPool {
-	return &BufioWriterPool{size: size}
-}
-
-func (bufPool *BufioWriterPool) Get(w io.Writer) *bufio.Writer {
-	return bufio.NewWriterSize(w, bufPool.size)
-}
-
-func (bufPool *BufioWriterPool) Put(b *bufio.Writer) {
-	b.Reset(nil)
-}
-
-func (bufPool *BufioWriterPool) NewWriteCloserWrapper(buf *bufio.Writer, w io.Writer) io.WriteCloser {
-	return ioutils.NewWriteCloserWrapper(w, func() error {
-		buf.Flush()
-		if writeCloser, ok := w.(io.WriteCloser); ok {
-			return writeCloser.Close()
-		}
-		return nil
-	})
-}