Auto merge of #80830 - Aaron1011:capture-token-empty-stack, r=petrochenkov
Auto merge of #80830 - Aaron1011:capture-token-empty-stack, r=petrochenkov

Use an empty `TokenCursorFrame` stack when capturing tokens

We will never need to pop  past our starting frame during token
capturing. Using an empty stack allows us to avoid pointless heap
allocations/deallocations.

aidancully/rust,graydon/rust,aidancully/rust,aidancully/rust,graydon/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,graydon/rust