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] `./mach build -d` does not report any errors
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- [X] These changes fix #36108 

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

components/script/serviceworker_manager.rs

@@ -321,7 +321,7 @@ impl ServiceWorkerManager {
 
     /// <https://w3c.github.io/ServiceWorker/#register-algorithm>
     fn handle_register_job(&mut self, mut job: Job) {
-        if !job.script_url.is_origin_trustworthy() {
+        if !job.script_url.origin().is_potentially_trustworthy() {
             // Step 1.1
             let _ = job
                 .client