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/windowproxy.rs

@@ -307,6 +307,7 @@ impl WindowProxy {
             document.get_referrer_policy(),
             None, // Doesn't inherit secure context
             None,
+            false,
         );
         let load_info = AuxiliaryWebViewCreationRequest {
             load_data: load_data.clone(),
@@ -485,6 +486,11 @@ impl WindowProxy {
             Some(target_document) => target_document,
             None => return Ok(None),
         };
+        let has_trustworthy_ancestor_origin = if new {
+            target_document.has_trustworthy_ancestor_or_current_origin()
+        } else {
+            false
+        };
         let target_window = target_document.window();
         // Step 13, and 14.4, will have happened elsewhere,
         // since we've created a new browsing context and loaded it with about:blank.
@@ -517,6 +523,7 @@ impl WindowProxy {
                 referrer_policy,
                 Some(secure),
                 Some(target_document.insecure_requests_policy()),
+                has_trustworthy_ancestor_origin,
             );
             let history_handling = if new {
                 NavigationHistoryBehavior::Replace