Cherrypick "Allow universal access from file if flag is set and url is file scheme."

Fixes a crash in apps using
WebSettings.setAllowUniversalAccessFromFileURLs(true).

> BUG=449075
> TEST=content_unittests --gtest_filter=NavigationControllerTest.IsInPageNavigation
>
> Review URL: https://codereview.chromium.org/855883002
>
> Cr-Commit-Position: refs/heads/master@{#313051}

Change-Id: I7360997ae6eec0279c932be555bfcb097e2804a7
2 files changed