Fix incorrect handling of position extents.

* This bug was introduced in 5862f0a3.
1 job for master in 6 seconds (queued for 1 second)
Status Job ID Name Coverage
  Test
failed #18413
doxygen
pages

00:00:06

 
Name Stage Failure
failed
pages Test There has been a runner system failure, please try again
Running with gitlab-runner 13.8.0 (775dd39d)
on specific runner to build doxygen docu page bc9b68e2
Preparing the "docker" executor
Using Docker executor with image doxygen-builder ...
Pulling docker image doxygen-builder ...
WARNING: Failed to pull image with policy "if-not-present": Error response from daemon: pull access denied for doxygen-builder, repository does not exist or may require 'docker login': denied: requested access to the resource is denied (docker.go:147:2s)
ERROR: Job failed (system failure): failed to pull image "doxygen-builder" with specified policies [if-not-present]: Error response from daemon: pull access denied for doxygen-builder, repository does not exist or may require 'docker login': denied: requested access to the resource is denied (docker.go:147:2s)