src/vs/workbench/api/browser/mainThreadLanguageFeatures.ts/MainThreadLanguageFeatures/$registerDocumentHighlightProvider
class MainThreadLanguageFeatures:	$registerDocumentHighlightProvider(handle: number, selector: IDocumentFilterDto[]): void {
		this._registrations.set(handle, this._languageFeaturesService.documentHighlightProvider.register(selector, <languages.DocumentHighlightProvider>{
			provideDocumentHighlights: (model: ITextModel, position: EditorPosition, token: CancellationToken): Promise<languages.DocumentHighlight[] | undefined> => {
				return this._proxy.$provideDocumentHighlights(handle, model.uri, position, token);
			}
		}));
	}