Adjust page mobile-like behavior in tablet mode

This prevents using the mobile-viewport and the
Android-style scrollbars for pages in tablet mode.
This gives a better UX on tablets and prevents
unexpected page layout changes when switching to
tablet mode.

TEST=Manually by visiting
     and switching to tablet mode. Page layout should
     not change to the mobile one, and ChromeOS
     scrollbars should remain in use.
     Also modified modified browser_tests.

Change-Id: Id858c03d37515f48b0f3515f099853999e3aafdd
Reviewed-by: Mitsuru Oshima <>
Commit-Queue: Ahmed Fakhry <>
Cr-Commit-Position: refs/heads/master@{#575732}
2 files changed