getTrailingCommentRanges returns comments at the start of the file

[ajafff]

TypeScript Version: master

Code:

// one
// two

Expected behavior:

ts.getTrailingCommentRanges(text, 0) doesn't return a comment.
Both comments are parsed by ts.getLeadingCommentRanges(text, 0).

Actual behavior:

ts.getTrailingCommentRanges(text, 0) parses // one as a trailing comment.
ts.getLeadingCommentRanges(text, 0) parses both comments.

The special handling of position 0 should also affect trailing comments.
With the current behavior I have to remember to not parse trailing comment ranges at position 0 to avoid duplicates.

Related Issues:
This was part of #28489 where I first proposed changing this behavior.

/cc @rbuckton