Add depfile support to android build scripts

base/android/jni_generator/jni_generator.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.
 
 """Extracts native methods from a Java file and generates the JNI bindings.
 If you change this, please run and update the tests."""
 
 import collections
 import errno
 import optparse
 import os
 import re
 import string
 from string import Template
 import subprocess
 import sys
 import textwrap
 import zipfile
 
+CHROMIUM_SRC = os.path.join(
+    os.path.dirname(__file__), os.pardir, os.pardir, os.pardir)
+BUILD_ANDROID_GYP = os.path.join(
+    CHROMIUM_SRC, 'build', 'android', 'gyp')
+
+sys.path.append(BUILD_ANDROID_GYP)
+
+from util import build_utils
+
 
 class ParseError(Exception):
   """Exception thrown when we can't parse the input file."""
 
   def __init__(self, description, *context_lines):
     Exception.__init__(self)
     self.description = description
     self.context_lines = context_lines
 
   def __str__(self):
@@ skipping 1313 matching lines @@
   return os.sep.join(script_components[base_index:])
 
 
 def main(argv):
   usage = """usage: %prog [OPTIONS]
 This script will parse the given java source code extracting the native
 declarations and print the header file to stdout (or a file).
 See SampleForTests.java for more details.
   """
   option_parser = optparse.OptionParser(usage=usage)
+  build_utils.AddDepfileOption(option_parser)
+
   option_parser.add_option('-j', '--jar_file', dest='jar_file',
                            help='Extract the list of input files from'
                            ' a specified jar file.'
                            ' Uses javap to extract the methods from a'
                            ' pre-compiled class. --input should point'
                            ' to pre-compiled Java .class files.')
   option_parser.add_option('-n', dest='namespace',
                            help='Uses as a namespace in the generated header '
                            'instead of the javap class name, or when there is '
                            'no JNINamespace annotation in the java source.')
@@ skipping 54 matching lines @@
     return 1
   output_file = None
   if options.output_dir:
     root_name = os.path.splitext(os.path.basename(input_file))[0]
     output_file = os.path.join(options.output_dir, root_name) + '_jni.h'
   if options.jarjar:
     with open(options.jarjar) as f:
       JniParams.SetJarJarMappings(f.read())
   GenerateJNIHeader(input_file, output_file, options)
 
+  if options.depfile:
+    build_utils.WriteDepfile(
+        options.depfile,
+        build_utils.GetPythonDependencies())
+
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))