in gr-editor/gr-editor.js [143:157]
_initializeMirror() {
return new Promise((resolve, reject) => {
this._importCodeMirror().then(() => {
const params = this.getCodeMirrorParams(
this.fileType,
this.fileContent,
this.prefs
);
this.mirror = this.$.codemirror;
this.mirror.setParams(params);
this._addEventListeners();
resolve();
});
});
}