Line counters: do not wrap when over 999 on mobile
Create a very long Diff with soooo much lines (e.g. 1000+).
Reduce the window and check that line numbers do not wrap anymore.
Reviewers: O1 Blessed Committers, avivey
Reviewed By: O1 Blessed Committers, avivey
Subscribers: tobiaswiese, Matthew, Cigaryno
Maniphest Tasks: T15615
Differential Revision: https://we.phorge.it/D25407