With PlzNavigate, we currently use a dirty hack to commit navigation inside
blink. It is temporarily. After the navigation has been done in the browser, it
is committed inside the renderer. The browser sends a request to the renderer,
but in a way, it is the response. It is essentially a request with a few
attributes that tells the renderer that it doesn't have to submit a new network
request and where it can find the response.
So 2 requests are made, one for the request and one for the "response".

For the second request, the renderer doesn't know if the request was submitted
from an isolated world and it will block the request if we don't prevent it to
do so.

This bug will be solved when one of these solutions is true:
1) When PlzNavigate will use a more elegant way to send a response into the renderer
2) If shouldContinueForNavigationPolicy call is disabled when the request is a
   response.
3) If shouldCheckMainWorldContentSecurityPolicy is sent back to the renderer.