parameters: (self, expectations_dir, expected_name, updated_name,
                   skpdiff_path)
docstring: @param expectations_dir   The directory to traverse for results files.
                 This should resemble expectations/gm in the Skia trunk.
          @param expected_name      The name of the expected result files. These
                 are in the format of expected-results.json.
          @param updated_name       The name of the updated expected result files.
                 Normally this matches --expectations-filename-output for the
                 rebaseline.py tool.
          @param skpdiff_path       The path used to execute the skpdiff command.
function: def __init__(self, expectations_dir, expected_name, updated_name,
                   skpdiff_path):
          """
          @param expectations_dir   The directory to traverse for results files.
                 This should resemble expectations/gm in the Skia trunk.
          @param expected_name      The name of the expected result files. These
                 are in the format of expected-results.json.
          @param updated_name       The name of the updated expected result files.
                 Normally this matches --expectations-filename-output for the
                 rebaseline.py tool.
          @param skpdiff_path       The path used to execute the skpdiff command.
          """
          self._expectations_dir = expectations_dir
          self._expected_name = expected_name
          self._updated_name = updated_name
          self._skpdiff_path = skpdiff_path
          self._generate_gm_comparison()
function_tokens: def __init__ ( self , expectations_dir , expected_name , updated_name , skpdiff_path ) : self . _expectations_dir = expectations_dir self . _expected_name = expected_name self . _updated_name = updated_name self . _skpdiff_path = skpdiff_path self . _generate_gm_comparison ( )