If the legacy configuration is only enabled if there are no other
configurations, defining a configuration in an imported library can lead to
unwanted results. For example, code that uses `any(MyTaintKind t).taints(node)`
would *stop* working, if it did not define its own configuration. (this actually
happened to us)
We performed a dist-compare to ensure there is not a performance deg ration by
doing this. Results at https://git.semmle.com/gist/rasmuswl/a1eca07f3a92f5f65ee78d733e5d260e
Tests that were affected by this:
- RockPaperScissors + Simple: new edges because no configuration was defined for
SqlInjectionTaint or CommandInjectionTaint
- CleartextLogging + CleartextStorage: new edges because no configuration was
defined before, AND duplicate deges.
- TestNode: new edges because no configuration was defined before
- PathInjection: Duplicate edges
- TarSlip: Duplicate edges
- CommandInjection: Duplicate edges
- ReflectedXss: Duplicate edges
- SqlInjection: Duplicate edges
- CodeInjection: Duplicate edges
- StackTraceExposure: Duplicate edges
- UnsafeDeserialization: Duplicate edges
- UrlRedirect: Duplicate edges
