Change Linux sysroot creator scripts to use XZ compression.

build/linux/sysroot_scripts/sysroot-creator.sh

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 #
 # This script should not be run directly but sourced by the other
 # scripts (e.g. sysroot-creator-jessie.sh).  Its up to the parent scripts
 # to define certain environment variables: e.g.
 #  DISTRO=ubuntu
 #  DIST=jessie
 #  # Similar in syntax to /etc/apt/sources.list
@@ skipping 137 matching lines @@
   for tool in ${REQUIRED_TOOLS} ; do
     if ! which ${tool} > /dev/null ; then
       echo "Required binary $tool not found."
       echo "Exiting."
       exit 1
     fi
   done
 
   # This is where the staging sysroot is.
   INSTALL_ROOT="${BUILD_DIR}/${DIST}_${ARCH_LOWER}_staging"
-  TARBALL="${BUILD_DIR}/${DISTRO}_${DIST}_${ARCH_LOWER}_sysroot.tgz"
+  TARBALL="${BUILD_DIR}/${DISTRO}_${DIST}_${ARCH_LOWER}_sysroot.tar.xz"
 
   if ! mkdir -p "${INSTALL_ROOT}" ; then
     echo "ERROR: ${INSTALL_ROOT} can't be created."
     exit 1
   fi
 }
 
 
 ChangeDirectory() {
   # Change directory to where this script is.
   cd ${SCRIPT_DIR}
 }
 
 
 ClearInstallDir() {
   Banner "Clearing dirs in ${INSTALL_ROOT}"
   rm -rf ${INSTALL_ROOT}/*
 }
 
 
 CreateTarBall() {
   Banner "Creating tarball ${TARBALL}"
-  tar zcf ${TARBALL} -C ${INSTALL_ROOT} .
+  tar Jcf ${TARBALL} -C ${INSTALL_ROOT} .
 }
 
 ExtractPackageGz() {
   local src_file="$1"
   local dst_file="$2"
   local repo="$3"
   gunzip -c "${src_file}" | egrep '^(Package:|Filename:|SHA256:) ' |
     sed "s|Filename: |Filename: ${repo}|" > "${dst_file}"
 }
 
@@ skipping 670 matching lines @@
   echo "    $0 help"
   exit 1
 else
   ChangeDirectory
   if echo $1 | grep -qs --regexp='\(^Print\)\|\(All$\)'; then
     "$@"
   else
     RunCommand "$@"
   fi
 fi