mq: remove early wlock release in qnew
It seems like something that missed the refactoring in
97b734fb9c6f.
mq: use .invalidate to cancel dirty mq state when cancelling transaction
Before the code optimistically relied on savedirty not being called a cancelled
transaction. If it was called it could save incorrect data.
Instead we now start using the invalidate method introduced in
b169ba60eebe.
mq: make qsave implementation more explicit
It wasn't obvious from the code how qsave mocked around with .hg/patches and
.hg/patches.? and what was going on.
This makes it more explicit so it will survive future refactorings.