stream performance optimizations

package com.fsck.k9.mailstore;

import java.io.BufferedInputStream;

import java.io.ByteArrayInputStream;

import java.io.File;

import java.io.FileInputStream;

        try {

            if (file != null) {

                Log.d(K9.LOG_TAG, "Decrypted data is file-backed.");

                return new FileInputStream(file);

                return new BufferedInputStream(new FileInputStream(file));

            }

            if (data != null) {

                Log.d(K9.LOG_TAG, "Decrypted data is memory-backed.");

import com.fsck.k9.mail.internet.TextBody;

import com.fsck.k9.mailstore.CryptoResultAnnotation;

import com.fsck.k9.mailstore.CryptoResultAnnotation.CryptoError;

import com.fsck.k9.mailstore.MimePartStreamParser;

import com.fsck.k9.mailstore.LocalMessage;

import com.fsck.k9.mailstore.MessageHelper;

import org.apache.commons.io.IOUtils;

import com.fsck.k9.mailstore.MimePartStreamParser;

import com.fsck.k9.provider.DecryptedFileProvider;

import com.fsck.k9.service.FileProviderInterface;

import org.apache.commons.io.IOUtils;

import org.openintents.openpgp.IOpenPgpService2;

import org.openintents.openpgp.OpenPgpDecryptionResult;

import org.openintents.openpgp.OpenPgpError;

package org.openintents.openpgp.util;

import java.io.BufferedInputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

    public static <T> DataSinkTransferThread<T> asyncPipeToDataSink(

            OpenPgpDataSink<T> dataSink, ParcelFileDescriptor output) throws IOException {

        InputStream inputStream = new BufferedInputStream(new AutoCloseInputStream(output));

        DataSinkTransferThread<T> dataSinkTransferThread =

                new DataSinkTransferThread<T>(dataSink, new AutoCloseInputStream(output));

                new DataSinkTransferThread<T>(dataSink, inputStream);

        dataSinkTransferThread.start();

        return dataSinkTransferThread;

    }