Remove an unnecessary loop when converting scheme in NavigatorContentUtils

This CL is simple refactoring in order not to use an unnecessary loop
in isSchemeWhitelisted() function.

Additionally the spec url is updated because current one is outdated.

TEST=http/tests/navigatorcontentutils
BUG=none

Review-Url: https://codereview.chromium.org/2083363003
Cr-Commit-Position: refs/heads/master@{#401832}
2 files changed