Keep magic wrappers from causing themselves to be torn down during reset

The realm of wrappers and magic is indeed magically wrapped. I haven't entirely wrapped my head around what different wrappers are supposed to do, but I did track down what was causing the error in #1342. The wrapper gets `reset` during `pop` when `set` is called on the viewmodel. During `reset`, the wrapper calls `mark`, which calls `clearCache`, which tears down wrappers if not advised not to. I'm not positive that the magic `reset` isn't wrong, but passing `dontTeardownWrappers` through `mark` to `clearCache` resolves this issue.

Fixes #1342