Process a list of paths which were added/removed/updated, making any
            necessary changes to the directory:
                - For an AnalysisDirectory, nothing needs to be changed, since
                  the mapping from source file to analysis file is 1:1.
                - For a SharedAnalysisDirectory, the symbolic links (as well as
                  the reverse-mapping we track) need to be updated to account for
                  new and deleted files.

            Return a list of files (corresponding to the given paths) that Pyre
            should be tracking.

def process_updated_files(self, paths: List[str]) -> List[str]:
        """
            Process a list of paths which were added/removed/updated, making any
            necessary changes to the directory:
                - For an AnalysisDirectory, nothing needs to be changed, since
                  the mapping from source file to analysis file is 1:1.
                - For a SharedAnalysisDirectory, the symbolic links (as well as
                  the reverse-mapping we track) need to be updated to account for
                  new and deleted files.

            Return a list of files (corresponding to the given paths) that Pyre
            should be tracking.
        """
        return [path for path in paths if self._is_tracked(path)]