DataModelRoot+TrigOutputHandling: More adjustment of thread-safe markings.

The TScopeAdapter constructor was marked as not-thread-safe, due to its manipulation of the default error level. However, calls to this constructor were not being properly checked due to an issue with the checker.

That issue is now being fixed, but that means that we now have some warnings from these calls.

Clean up a bit by splitting the constructor in two. One doesn't have the quiet option and can be considered thread-safe, while one which takes a quiet argument is still marked as not thread-safe. Adjust calls appropriately.

We can also clean up the implementation a bit.

In TrigOutputHandling: Use RootType::ByName1 instead of RootType::ByName. The latter suppresses errors but has to be tagged as not thread-safe. We shouldn't be expecting to get errors from these calls anyway.