iOS 中 popUntil没有考虑native的情况

native1 -> fluuter1 -> native2-> fluuter2 -> native3 -> fluuter3 -> native4 -> fluuter4
然后 popUntil 到 fluuter1 会有问题，从源码中看。一共执行了执行了 3 次 nativeRouterApi.popRoute 操作。但是这三次操作只能pop到 native3 。
即便是更改了 BoostDelegate 中 popRoute 的实现，来判断 navigationController.viewControllers 中的 element 是否是flutter还是native，但是 native2 根本没办法判断，因为 native2 的pop没有调用

BOOL popDid = NO;
FBFlutterViewContainer *fbVC = self.navigationController.viewControllers.lastObject;
if ([fbVC isKindOfClass:FBFlutterViewContainer.class] && [fbVC.name isEqualToString:options.pageName]) {
[self.navigationController popViewControllerAnimated:animated];
popDid = YES;
}

if (popDid == NO) {
NSArray *tempVcs = self.navigationController.viewControllers;
for (long i = tempVcs.count-1; i>=0; i--) {
FBFlutterViewContainer *fbVC = tempVcs[i];
if ([fbVC isKindOfClass:FBFlutterViewContainer.class] && [fbVC.name isEqualToString:options.pageName]) {
[self.navigationController popViewControllerAnimated:animated];
break;
} else {
[self.navigationController popViewControllerAnimated:NO];
}
}
}

如果想实现完全的 popUntil 方法，需要在 targetContainer?.navigator?.popUntil(ModalRoute.withName(targetPage.name))); 前调用 nativeRouterApi.popRoute 并添加特殊参数来区分popUntil。或者 调用 nativeRouterApi.popUntil 了，这种情况下需要添加 popUntil 桥接

Start by tracing BoostDelegate, nativeRouterApi.popRoute, and the iOS navigationController.viewControllers handling described in the issue. Compare that flow with targetContainer?.navigator?.popUntil(ModalRoute.withName(targetPage.name)) and the proposed nativeRouterApi.popUntil bridge; done means popUntil reaches the requested Flutter route across interleaved native and Flutter containers.

Written by the indexing model from the issue text.