Option added to protobuf build for import directories

tools/protoc_wrapper/protoc_wrapper.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.
 
 """
 A simple wrapper for protoc.
 Script for //third_party/protobuf/proto_library.gni .
 Features:
 - Inserts #include for extra header automatically.
@@ skipping 71 matching lines @@
                       help="Output directory for custom generator plugin.")
 
   parser.add_argument("--plugin",
                       help="Relative path to custom generator plugin.")
   parser.add_argument("--plugin-options",
                       help="Custom generator plugin options.")
   parser.add_argument("--cc-options",
                       help="Standard C++ generator options.")
   parser.add_argument("--include",
                       help="Name of include to insert into generated headers.")
-
+  parser.add_argument("--import-dir", action="append", default=[],
+                      help="Extra import directory for protos, can be repeated."
+  )
   parser.add_argument("protos", nargs="+",
                       help="Input protobuf definition file(s).")
 
   options = parser.parse_args()
 
   proto_dir = os.path.relpath(options.proto_in_dir)
   protoc_cmd = [os.path.realpath(options.protoc)]
 
   protos = options.protos
   headers = []
@@ skipping 11 matching lines @@
       headers.append(os.path.join(cc_out_dir, stripped_name + ".pb.h"))
 
   if options.plugin_out_dir:
     plugin_options = FormatGeneratorOptions(options.plugin_options)
     protoc_cmd += [
       "--plugin", "protoc-gen-plugin=" + os.path.relpath(options.plugin),
       "--plugin_out", plugin_options + options.plugin_out_dir
     ]
 
   protoc_cmd += ["--proto_path", proto_dir]
+  for path in options.import_dir:
+    protoc_cmd += ["--proto_path", path]
+
   protoc_cmd += [os.path.join(proto_dir, name) for name in protos]
+
   ret = subprocess.call(protoc_cmd)
   if ret != 0:
     raise RuntimeError("Protoc has returned non-zero status: "
                        "{0} .".format(ret))
 
   if options.include:
     WriteIncludes(headers, options.include)
 
 
 if __name__ == "__main__":
   try:
     main(sys.argv)
   except RuntimeError as e:
     print(e, file=sys.stderr)
     sys.exit(1)