Auto merge of #11644 - asajeffrey:mozbrowser-top-level-browsing-context, r=ConnerGBrewster

Mozbrowser top level browsing context

<!-- Please describe your changes on the following line: -->
Got `window.top` and `window.parent` to return the right result inside a `mozbrowser` iframe.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] There are tests for these changes

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1 files changed, 1 insertions, 1 deletions

diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index a3a9d4beeaa..2a7466dc2eb 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -1260,7 +1260,7 @@ impl Document {
 
     pub fn trigger_mozbrowser_event(&self, event: MozBrowserEvent) {
         if mozbrowser_enabled() {
-            if let Some((containing_pipeline_id, subpage_id)) = self.window.parent_info() {
+            if let Some((containing_pipeline_id, subpage_id, _)) = self.window.parent_info() {
                 let event = ConstellationMsg::MozBrowserEvent(containing_pipeline_id,
                                                               subpage_id,
                                                               event);