Check all ancestor navigable trustworthiness for mixed content (#36157)

Propagate through documents a flag that represents if any of the
ancestor navigables has a potentially trustworthy origin.

The "potentially trustworthy origin" concept appears to have gotten
confused in a couple of places and we were instead testing if a URL had
"potentially trustworthy" properties.

The main test for the ancestor navigables is
[mixed-content/nested-iframes](https://github.com/web-platform-tests/wpt/blob/master/mixed-content/nested-iframes.window.js)

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- [X] These changes fix #36108 

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---------

Signed-off-by: Sebastian C <sebsebmc@gmail.com>

components/net/http_loader.rs

@@ -1010,7 +1010,7 @@ pub async fn http_redirect_fetch(
     // Step 8: Increase request’s redirect count by 1.
     request.redirect_count += 1;
 
-    // Step 7
+    // Step 9
     let same_origin = match request.origin {
         Origin::Origin(ref origin) => *origin == location_url.origin(),
         Origin::Client => panic!(