[Android WebAPK] Enable WebAPKs to handle non HTTP/HTTPS deep links

This CL changes the sanity checks in HostBrowserLauncherParams to
enable WebAPKs to handle non HTTP/HTTPs deep links as long as
the URL is rewritten to a HTTP/HTTPS URL.

BUG=893757
TEST=MainActivityTest.testIntetnUrlOutOfScopeBecauseOfScheme

Change-Id: I1c88326024129f95cdc7abc12ea7d042f6ad24e9
Reviewed-on: https://chromium-review.googlesource.com/c/1271938
Commit-Queue: Peter Kotwicz <pkotwicz@chromium.org>
Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#598107}