Rewrite isolate_smoke_test.py to increase the coverage.

tools/isolate/data/isolate/touch_root.py

Index: tools/isolate/data/isolate/touch_root.py
diff --git a/tools/isolate/data/isolate/touch_root.py b/tools/isolate/data/isolate/touch_root.py
new file mode 100755
index 0000000000000000000000000000000000000000..1d014fc208e642b2baa3bb98355fcbe21f21cf57
--- /dev/null
+++ b/tools/isolate/data/isolate/touch_root.py
@@ -0,0 +1,24 @@
+#!/usr/bin/env python
+# Copyright (c) 2012 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.
+
+import os
+import sys
+
+
+def main():
+  print 'child_touch_root: Verify the relative directories'
+  root_dir = os.path.dirname(os.path.abspath(__file__))
+  parent_dir, base = os.path.split(root_dir)
+  parent_dir, base2 = os.path.split(parent_dir)
+  if base != 'isolate' or base2 != 'data':
+    print 'Invalid root dir %s' % root_dir
+    return 4
+
+  open(os.path.join(parent_dir, 'isolate.py'), 'r').close()
+  return 0
+
+
+if __name__ == '__main__':
+  sys.exit(main())