Update the linux ARM root image.

This brings in precise security updates which fixes the
linux ARM cross build.  The image itself was updated to
include these in the following NaCl CL:

https://codereview.chromium.org/25041003/

BUG=255241
TEST=linux_arm_cross_compile bot
R=bradnelson@google.com

Review URL: https://codereview.chromium.org/25000006

git-svn-id: http://src.chromium.org/svn/trunk/src/build@226019 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

linux/install-arm-sysroot.py

@@ -3,16 +3,27 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-# Script to install ARM root image for cross building of ARM chrome on linux.
-# This script can be run manually but is more often run as part of gclient
-# hooks. When run from hooks this script should be a no-op on non-linux
-# platforms.
+"""Script to install ARM root image for cross building of ARM chrome on linux.
+This script can be run manually but is more often run as part of gclient
+hooks. When run from hooks this script should be a no-op on non-linux
+platforms.
 
-# The sysroot image could be constructed from scratch based on the current
-# state or precise/arm but for consistency we currently use a pre-built root
-# image which was originally designed for building trusted NaCl code. The image
-# will normally need to be rebuilt every time chrome's build dependancies are
-# changed.
+The sysroot image could be constructed from scratch based on the current
+state or precise/arm but for consistency we currently use a pre-built root
+image which was originally designed for building trusted NaCl code. The image
+will normally need to be rebuilt every time chrome's build dependancies are
+changed.
+
+Steps to rebuild the arm sysroot image:
+
+- cd $SRC/native_client
+- ./tools/trusted_cross_toolchains/trusted-toolchain-creator.armel.precise.sh \
+    UpdatePackageLists
+- ./tools/trusted_cross_toolchains/trusted-toolchain-creator.armel.precise.sh \
+    BuildJail $SRC/out/arm-sysroot.tar.gz
+- gsutil cp -a public-read $SRC/out/arm-sysroot.tar.gz \
+    nativeclient-archive2/toolchain/$NACL_REV/naclsdk_linux_arm-trusted.tgz
+"""
 
 import os
 import shutil
@@ -23,7 +34,7 @@ import sys
 SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
 URL_PREFIX = 'https://commondatastorage.googleapis.com'
 URL_PATH = 'nativeclient-archive2/toolchain'
-REVISION = 10991
+REVISION = 12203
 TARBALL = 'naclsdk_linux_arm-trusted.tgz'