src/vs/workbench/api/browser/mainThreadEditorTabs.ts/MainThreadEditorTabs/constructor
class MainThreadEditorTabs:	constructor(
		extHostContext: IExtHostContext,
		@IEditorGroupsService private readonly _editorGroupsService: IEditorGroupsService,
		@IEditorService editorService: IEditorService
	) {

		this._proxy = extHostContext.getProxy(ExtHostContext.ExtHostEditorTabs);

		this._editorGroupsService.whenReady.then(() => this._editorGroupsService.groups.forEach(this._subscribeToGroup, this));
		this._dispoables.add(_editorGroupsService.onDidAddGroup(this._subscribeToGroup, this));
		this._dispoables.add(_editorGroupsService.onDidRemoveGroup(e => {
			const subscription = this._groups.get(e);
			if (subscription) {
				subscription.dispose();
				this._groups.delete(e);
				this._pushEditorTabs();
			}
		}));
		this._dispoables.add(editorService.onDidActiveEditorChange(this._pushEditorTabs, this));
		this._pushEditorTabs();
	}