Add ARM toolchain support.

libraries/ffmpeg-0.5/nacl-ffmpeg-0.5.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.
 
 # nacl-ffmpeg-0.5.sh
 #
 # usage:  nacl-ffmpeg-0.5.sh
 #
 # this script downloads, patches, and builds ffmpeg for Native Client 
 #
 
 readonly URL=http://commondatastorage.googleapis.com/nativeclient-mirror/nacl/ffmpeg-0.5.tar.bz2
 #readonly URL=http://ffmpeg.org/releases/ffmpeg-0.5.tar.bz2
 readonly PATCH_FILE=nacl-ffmpeg-0.5.patch
 readonly PACKAGE_NAME=ffmpeg-0.5
 
 source ../../build_tools/common.sh
 
 
 CustomConfigureStep() {
   export PKG_CONFIG_PATH=${NACL_SDK_USR_LIB}/pkgconfig
   export PKG_CONFIG_LIBDIR=${NACL_SDK_USR_LIB}
   export PATH=${NACL_BIN_PATH}:${PATH};
   MakeDir ${NACL_PACKAGES_REPOSITORY}/${PACKAGE_NAME}/${PACKAGE_NAME}-build
   ChangeDir ${NACL_PACKAGES_REPOSITORY}/${PACKAGE_NAME}/${PACKAGE_NAME}-build
   local extra_args=""
-  if [ "${NACL_PACKAGES_BITSIZE}" == pnacl ]; then
+  if [ "${NACL_ARCH}" = pnacl ]; then
     extra_args="--cc=pnacl-clang --arch=pnacl"
   fi
   ../configure \
     --cross-prefix=${NACL_CROSS_PREFIX}- \
     ${extra_args} \
     --target-os=linux \
     --enable-gpl \
     --enable-static \
     --enable-cross-compile \
     --disable-shared \
@@ skipping 37 matching lines @@
   DefaultPatchStep
   CustomConfigureStep
   CustomPostConfigureStep
   CustomBuildAndInstallStep
   DefaultCleanUpStep
 }
 
 
 CustomPackageInstall
 exit 0