Remove unused imports from tools/js2c.py

tools/js2c.py

 #!/usr/bin/env python
 #
 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
@@ skipping 13 matching lines @@
 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 # This is a utility for converting JavaScript source code into C-style
 # char arrays. It is used for embedded JavaScript code in the V8
 # library.
 
-import os, re, sys, string
+import os, re
 import optparse
 import jsmin
-import bz2
 import textwrap
 
 
 class Error(Exception):
   def __init__(self, msg):
     Exception.__init__(self, msg)
 
 
 def ToCArray(byte_sequence):
   result = []
@@ skipping 548 matching lines @@
   JS2C(args[2:],
        args[0],
        args[1],
        options.raw,
        options.startup_blob,
        options.js)
 
 
 if __name__ == "__main__":
   main()