[DAS] Fixes quotes conversion to work the same everywhere

Fixes: #60218

Change-Id: Id249ff553cd500c827894a5a94a280f49f86a132
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/412321
Reviewed-by: Phil Quitslund <[email protected]>
Reviewed-by: Lasse Nielsen <[email protected]>
Commit-Queue: Phil Quitslund <[email protected]>
Auto-Submit: Felipe Morschel <[email protected]>

Author: FMorschel