Re-land: Instrumented libraries: add a target for pre-built libraries.

third_party/instrumented_libraries/scripts/unpack_binaries.sh

Index: third_party/instrumented_libraries/scripts/unpack_binaries.sh
diff --git a/third_party/instrumented_libraries/scripts/unpack_binaries.sh b/third_party/instrumented_libraries/scripts/unpack_binaries.sh
new file mode 100755
index 0000000000000000000000000000000000000000..12af6adc578208026f640095ac895539497498c5
--- /dev/null
+++ b/third_party/instrumented_libraries/scripts/unpack_binaries.sh
@@ -0,0 +1,15 @@
+#!/bin/bash
+# Copyright 2015 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.
+
+# Unpacks an archive containing prebuilt instrumented libraries into output dir.
+
+archive_file=$1
+target_dir=$2
+stamp_file=$3
+
+rm ${target_dir}/* -rf
+tar -zxf ${archive_file} -C ${target_dir}
+
+touch ${stamp_file}