bundle: highlight misbehavior when --base does not match any revision See next changeset for fix and details.

branching: merge with stable I need the fix to `generate-churning-bundle.py`.

generate-churning-bundle: fix script for python3 This script has apparently not run for a long time.

narrow: strip trailing `/` from manifest dir before matching it Commit 17a822d7943e broke some of our internal tests at Google because the `dir` variable contains a trailing slash since that commit. Let's restore the old behavior by stripping that trailing slash.

tests: demonstrate error when narrowing with `rootfilesin:` pattern This demonstrates a bug introduced in 17a822d7943e.

matchers: use correct method for finding index in vector The path matcher has an optimization for when all paths are `rootfilesin:`. This optimization exists in both Python and Rust. However, the Rust implementation currently has a bug that makes it fail in most cases. The bug is that it `rfind()` where it was clearly intended to use `rposition()`. This patch fixes that and adds a test.

dirstate: make the `transaction` argument of `setbranch` mandatory This is deprecated since 6.4. We should drop it now.

rust-clippy: apply some more trivial fixes All of these were hinted at by clippy and make the code simpler.

rust-clippy: simplify `match` to `if let` This was hinted at by clippy, and makes it more obvious that nothing is happening in the `None` case.

censor: accept multiple revision in a single call This is useful when dealing with corruption, as all the corrupted revision can be dealt with in one go.