src/vs/workbench/api/common/extHostLanguageFeatures.ts/DeclarationAdapter/provideDeclaration
class DeclarationAdapter:	provideDeclaration(resource: URI, position: IPosition, token: CancellationToken): Promise<modes.LocationLink[]> {
		const doc = this._documents.getDocument(resource);
		const pos = typeConvert.Position.to(position);
		return asPromise(() => this._provider.provideDeclaration(doc, pos, token)).then(convertToLocationLinks);
	}