function _watchProjectRoot(rootPath) {
        FileSystem.on("change", _fileSystemChange);
        FileSystem.on("rename", _fileSystemRename);

        FileSystem.watch(FileSystem.getDirectoryForPath(rootPath), ProjectModel._shouldShowName, ProjectModel.defaultIgnoreGlobs, function (err) {
            if (err === FileSystemError.TOO_MANY_ENTRIES) {
                if (!_projectWarnedForTooManyFiles) {
                    _showErrorDialog(ERR_TYPE_MAX_FILES);
                    _projectWarnedForTooManyFiles = true;
                }
            } else if (err) {
                console.error("Error watching project root: ", rootPath, err);
            }
        });

        // Reset allFiles cache
        model._resetCache();
    }
@private

Watches the project for filesystem changes so that the tree can be updated.