The matcher is allowed to return null per
https://angular.io/api/router/UrlMatcher#usage-notes
And run `yarn gulp format` to pick up recent clang format changes.
Closes#29824
BREAKING CHANGE: UrlMatcher's type now reflects that it could always return
null.
If you implemented your own Router or Recognizer class, please update it to
handle matcher returning null.
PR Close#36402
Moves the public api .d.ts files from tools/public_api_guard to
goldens/public-api.
Additionally, provides a README in the goldens directory and a script
assist in testing the current state of the repo against the goldens as
well as a command for accepting all changes to the goldens in a single
command.
PR Close#35768