Rollup merge of #80898 - JohnTitor:vecdeque-another-case, r=lcnr
Rollup merge of #80898 - JohnTitor:vecdeque-another-case, r=lcnr

Add another test case for #79808

Taken from #80293.
Closes #80293

r? `@lcnr`

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