Get rid of the data socket completely when data transfer is finished.

Fixes an FTP transaction hang when we wait for server's response
and the server apparently waits for us.

TEST=See bug.
http://crbug.com/21127

Review URL: http://codereview.chromium.org/192042

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@25750 0039d316-1c4b-4281-b951-d872f2087c98

net/ftp/ftp_network_transaction.cc

@@ -981,6 +981,10 @@ int FtpNetworkTransaction::DoDataRead() {
   DCHECK_GT(read_data_buf_len_, 0);
 
   if (data_socket_ == NULL || !data_socket_->IsConnected()) {
+    // If we don't destroy the data socket completely, some servers will wait
+    // for us (http://crbug.com/21127).
+    data_socket_.reset();
+
     // No more data so send QUIT Command now and wait for response.
     return Stop(OK);
   }