src/vs/editor/contrib/inlayHints/browser/inlayHints.ts/InlayHintItem/resolve
class InlayHintItem:	async resolve(token: CancellationToken): Promise<void> {
		if (typeof this.provider.resolveInlayHint !== 'function') {
			return;
		}
		if (this._currentResolve) {
			// wait for an active resolve operation and try again
			// when that's done.
			await this._currentResolve;
			if (token.isCancellationRequested) {
				return;
			}
			return this.resolve(token);
		}
		if (!this._isResolved) {
			this._currentResolve = this._doResolve(token)
				.finally(() => this._currentResolve = undefined);
		}
		await this._currentResolve;
	}