9b16c7a712
Don't encode file information for span with a dummy location Fixes #83112 The location information for a dummy span isn't real, so don't encode it. This brings the incr comp cache code into line with the Span `StableHash` impl, which doesn't hash the location information for dummy spans. Previously, we would attempt to load the 'original' file from a dummy span - if the file id changed (e.g. due to being moved on disk), we would get an ICE, since the Span was still valid due to its hash being unchanged.
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