Feature Request: Folding range for inactive regions

Feature Request

There are cases in which the extension emits symbol information but does not emit a corresponding folding range. This makes it more difficult and in some cases impossible for extensions to create advanced commands for folding and unfolding code.

Notice in this screenshot that the Outline contains symbols for both versions of foo. But if you look at the fold icons in the gutter there is no folding range associated with the inactive foo on line 2.

I have an extension that folds definitions without folding comments and preprocessor blocks. In order to do this I obtain the symbols for the document then assume they are valid folding ranges. While it's not an ideal approach it works in all cases so far except symbols inside inactive preprocessor blocks.

If the extension goes through the trouble of emitting a symbol it's desirable that it reliably produces a folding scope as well. In this specific case, even in the absence of my extension it's desirable for the first foo to fold.

No file, test, or entry point is named. Start by tracing how symbols and folding ranges are emitted for inactive preprocessor regions, then verify that the inactive foo receives a folding range while existing symbol behavior remains intact.