Cleanup most pylint errors in json_schema_compiler.

tools/json_schema_compiler/preview.py

 #!/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.
 """Server for viewing the compiled C++ code from tools/json_schema_compiler.
 """
 
 import cc_generator
 import code
@@ skipping 183 matching lines @@
                                  self.server.cpp_namespace_pattern)
     try:
       # Get main file.
       namespace = schema_loader.ResolveNamespace(filename)
       type_generator = cpp_type_generator.CppTypeGenerator(
            api_model,
            schema_loader,
            namespace)
 
       # Generate code
-      cpp_namespace = 'generated_api_schemas'
       if file_ext == '.h':
         cpp_code = (h_generator.HGenerator(type_generator)
             .Generate(namespace).Render())
       elif file_ext == '.cc':
         cpp_code = (cc_generator.CCGenerator(type_generator)
             .Generate(namespace).Render())
       else:
         self.send_error(404, "File not found: %s" % request_path)
         return
 
@@ skipping 64 matching lines @@
       path = os.curdir
 
     # Firstly, a .. link if this isn't the root.
     if not os.path.samefile(os.curdir, path):
       normpath = os.path.normpath(os.path.join(path, os.pardir))
       html.Append('<li><a href="/%s">%s/</a>' % (normpath, os.pardir))
 
     # Each file under path/
     for filename in sorted(os.listdir(path)):
       full_path = os.path.join(path, filename)
-      (file_root, file_ext) = os.path.splitext(full_path)
+      file_ext = os.path.splitext(full_path)[1]

[not at google - send to devlin, 2015/01/14 22:44:41]

ditto

       if os.path.isdir(full_path) and not full_path.endswith('.xcodeproj'):
         html.Append('<li><a href="/%s/">%s/</a>' % (full_path, filename))
       elif file_ext in ['.json', '.idl']:
         # cc/h panes will automatically update via the hash change event.
         html.Append('<li><a href="#%s">%s</a>' %
             (filename, filename))
 
     html.Append('</ul>')
 
     return html.Render()
@@ skipping 55 matching lines @@
       pass
 
     server = PreviewHTTPServer(('', int(opts.port)),
                                CompilerHandler,
                                highlighters,
                                include_rules,
                                opts.namespace)
     server.serve_forever()
   except KeyboardInterrupt:
     server.socket.close()