Candidate fix at https://chromium-review.googlesource.com/c/chromium/src/+/1048884.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/66278e5e8819aa7d4c0e69138010cfd0e63fbb93

commit 66278e5e8819aa7d4c0e69138010cfd0e63fbb93
Author: dpapad <dpapad@chromium.org>
Date: Wed May 09 01:43:56 2018

CrOS Network Settings: Apply shared styling to a few unstyled buttons.

Bug:  840591 
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I6fdde8fc17af9592cb2bb6d52a6ef476c50309ab
Reviewed-on: https://chromium-review.googlesource.com/1048884
Commit-Queue: Demetrios Papadopoulos <dpapad@chromium.org>
Reviewed-by: Michael Giuffrida <michaelpg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#557055}
[modify] https://crrev.com/66278e5e8819aa7d4c0e69138010cfd0e63fbb93/ui/webui/resources/cr_components/chromeos/network/network_apnlist.html
[modify] https://crrev.com/66278e5e8819aa7d4c0e69138010cfd0e63fbb93/ui/webui/resources/cr_components/chromeos/network/network_choose_mobile.html
[modify] https://crrev.com/66278e5e8819aa7d4c0e69138010cfd0e63fbb93/ui/webui/resources/cr_components/chromeos/network/network_siminfo.html