GitLab

BUG=369875
TEST=On a Chromebook, try to save a web page and see the file type selector.

Review URL: https://codereview.chromium.org/287083004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@270955 0039d316-1c4b-4281-b951-d872f2087c98