Export PrinterClass symbol

This symbol should be marked CHROMEOS_EXPORT since it is used from
the chrome.autotestPrivate api.


Change-Id: I9aa10741682a53ba9b6263aed0d4619663609d92
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1617560
Auto-Submit: Bailey Berro <baileyberro@chromium.org>
Reviewed-by: Sean Kau <skau@chromium.org>
Commit-Queue: Bailey Berro <baileyberro@chromium.org>
Cr-Commit-Position: refs/heads/master@{#661963}
1 file changed