Auto merge of #23887 - servo:jdm-patch-47, r=asajeffrey

Use origin of final HTTP response as document origin

I discovered surprising problems when loading pages from http://joshmatthews.net that load same-origin images and try to use them as webgl textures. Since there's a redirect from joshmatthews.net to www.joshmatthews.net, the images are not considered same-origin in Servo because the document stores the origin for the original request's URL, rather than the origin of the response that is received after processing any redirections.

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components/script/script_thread.rs

@@ -3128,7 +3128,7 @@ impl ScriptThread {
             incomplete.pipeline_id,
             incomplete.parent_info,
             incomplete.window_size,
-            origin,
+            origin.clone(),
             incomplete.navigation_start,
             incomplete.navigation_start_precise,
             self.webgl_chan.as_ref().map(|chan| chan.channel()),
@@ -3212,7 +3212,7 @@ impl ScriptThread {
             &window,
             HasBrowsingContext::Yes,
             Some(final_url.clone()),
-            incomplete.origin,
+            origin,
             is_html_document,
             content_type,
             last_modified,