[Android] Sever findbugs dependencies on environment variables.

tools/android/findbugs_plugin/test/run_findbugs_plugin_tests.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.
 
 # This is used to test the findbugs plugin, it calls
-# build/android/pylib/findbugs.py to analyze the classes in
+# build/android/pylib/utils/findbugs.py to analyze the classes in
 # org.chromium.tools.findbugs.plugin package, and expects to get the same
 # issue with those in expected_result.txt.
 #
 # Useful command line:
 # --rebaseline to generate the expected_result.txt, please make sure don't
 # remove the expected result of exsting tests.
 
 
 import optparse
 import os
 import sys
 
-lib_folder = os.path.join(os.getenv('CHROME_SRC'), 'build', 'android', 'pylib')
-if lib_folder not in sys.path:
-  sys.path.append(lib_folder)
+sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__),
+                                             '..', '..', '..', '..',
+                                             'build', 'android')))
 
-import findbugs
+from pylib import constants
+from pylib.utils import findbugs
 
 
 def main(argv):
-  if not findbugs.CheckEnvironment():
-    return 1
-
   parser = findbugs.GetCommonParser()
 
   options, _ = parser.parse_args()
 
-  chrome_src = os.getenv('CHROME_SRC')
-
   if not options.known_bugs:
-    options.known_bugs = os.path.join(chrome_src, 'tools', 'android',
+    options.known_bugs = os.path.join(constants.CHROME_DIR, 'tools', 'android',
                                       'findbugs_plugin', 'test',
                                       'expected_result.txt')
   if not options.only_analyze:
     options.only_analyze = 'org.chromium.tools.findbugs.plugin.*'
 
   return findbugs.Run(options)
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))