The tests in errorpage_browsertest.cc succeed for the Desktop layout, but will fail for the mobile layout.
The tests fail when checking IsDisplayingText(..., GetShowSavedButtonLabel()). The test uses a case-sensitive check (String.prototype.indexOf), but mobile and desktop layout differ in terms of capitalization (mobile makes buttons all-caps, desktop doesn't).
Performing a case-insensitive comparison should be sufficient to fix the test. This should be safe as long as the interstitial doesn't have the same strings appear twice with different cases.
Comment 1 by bugdroid1@chromium.org
, May 2 2017