That way we can also cache A-Z, 0-9, _, $ (and all others obviously).

Change-Id: I394001646c80bbabf9b09f66eddc1bef82ae91b3
Reviewed-on: https://chromium-review.googlesource.com/c/1341948
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57606}