function innerCallback(filePath)
        {
            if (!filePath) {
                callback(null);
                return;
            }
            createFilePath = filePath;
            if (!content) {
                contentSet.call(this);
                return;
            }
            this._fileSystem.setFileContent(filePath, content, contentSet.bind(this));
        }
@param {?string} filePath
@this {WebInspector.FileSystemWorkspaceBinding.FileSystem}