Part 3.3: Is policy list subsumed under subsuming policy?

In this patch we consider special case of `allow all inline`. In
particular, if the returned CSP allows all inline behavior but
Embedding-CSP does not, then the latter does not subsume the former.

BUG=647588

Review-Url: https://codereview.chromium.org/2536713002
Cr-Commit-Position: refs/heads/master@{#435930}
5 files changed