GitLab

Decode IDN hostnames in SecurityInterstitialPage before displaying
them. Add browser tests for SSLBlockingPage and
CaptivePortalBlockingPage to test this behavior. Other blocking pages
can subclass the new SecurityInterstitialIDNTest class to do similar
tests.

BUG=450883

Review URL: https://codereview.chromium.org/1000333003

Cr-Commit-Position: refs/heads/master@{#322128}