Validator_ragel: move checkdecoder test from Makefile to scons

src/trusted/validator_ragel/unreviewed/decoder_test_one_file.sh

 #!/bin/bash
 # Copyright (c) 2012 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Checks that a given assembyl file is decoded identically to objdump.
 #
 # Usage:
 #   decoder_test_one_file.sh GAS=... OBJDUMP=... DECODER=... ASMFILE=...
 
+# TODO(shcherbina): fix leaking temp files on failed tests
+
 set -e
 set -u
 
 # Parse arguments.
 eval "$@"
 
 # Sanity check arguments.
 if [[ ! -x "${GAS% *}" || ! -x "${OBJDUMP% *}" || ! -x "${DECODER% *}" ]] ; then
   echo >&2 "error: GAS or OBJDUMP or DECODER incorrect"
   exit 2
 fi
 
 if [[ ! -f "$ASMFILE" ]] ; then
   echo >&2 "error: ASMFILE is not a regular file: $ASMFILE"
   exit 3
 fi
 
 # Produce an object file, disassemble it in 2 ways and compare results.
 $GAS "$ASMFILE" -o "$ASMFILE.o"
 rm -f "$ASMFILE"
 $DECODER "$ASMFILE.o" > "$ASMFILE.decoder"
 # Take objdump output starting at line 8 to skip the unimportant header that
 # is not emulated in the decoder test.
 $OBJDUMP -d "$ASMFILE.o" |
   tail -n+8 - |
   cmp - "$ASMFILE.decoder"
 rm -f "$ASMFILE.o" "$ASMFILE.decoder"