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/script/dom/location.rs

@@ -126,6 +126,7 @@ impl Location {
             referrer_policy,
             None, // Top navigation doesn't inherit secure context
             Some(source_document.insecure_requests_policy()),
+            source_document.has_trustworthy_ancestor_origin(),
         );
         self.window
             .load_url(history_handling, reload_triggered, load_data, can_gc);