From 832f0ee2aea01da213ad948e94fdff72df6c9710 Mon Sep 17 00:00:00 2001
From: Stephen A Pohl <spohl.mozilla.bugs@gmail.com>
Date: Tue, 21 Apr 2020 12:31:51 +0000
Subject: [PATCH] Bug 1597508: Use WidgetUtils::DOMWindowToWidget to determine
 native window during reopen of Firefox on macOS. r=farre

Differential Revision: https://phabricator.services.mozilla.com/D71408
---
 toolkit/xre/nsNativeAppSupportCocoa.mm | 28 +++++++++-----------------
 1 file changed, 10 insertions(+), 18 deletions(-)

diff --git a/toolkit/xre/nsNativeAppSupportCocoa.mm b/toolkit/xre/nsNativeAppSupportCocoa.mm
index c43388b74281..f981dea8ac85 100644
--- a/toolkit/xre/nsNativeAppSupportCocoa.mm
+++ b/toolkit/xre/nsNativeAppSupportCocoa.mm
@@ -15,38 +15,30 @@
 #include "nsIBaseWindow.h"
 #include "nsCommandLine.h"
 #include "mozIDOMWindow.h"
-#include "nsIDocShellTreeItem.h"
-#include "nsIDocShellTreeOwner.h"
-#include "nsIInterfaceRequestorUtils.h"
 #include "nsIWebNavigation.h"
 #include "nsIWidget.h"
 #include "nsIWindowMediator.h"
+#include "nsPIDOMWindow.h"
+#include "WidgetUtils.h"
 
 // This must be included last:
 #include "nsObjCExceptions.h"
 
+using mozilla::widget::WidgetUtils;
+
 nsresult GetNativeWindowPointerFromDOMWindow(mozIDOMWindowProxy* a_window,
                                              NSWindow** a_nativeWindow) {
   *a_nativeWindow = nil;
   if (!a_window) return NS_ERROR_INVALID_ARG;
 
-  nsCOMPtr<nsIWebNavigation> mruWebNav(do_GetInterface(a_window));
-  if (mruWebNav) {
-    nsCOMPtr<nsIDocShellTreeItem> mruTreeItem(do_QueryInterface(mruWebNav));
-    nsCOMPtr<nsIDocShellTreeOwner> mruTreeOwner = nullptr;
-    mruTreeItem->GetTreeOwner(getter_AddRefs(mruTreeOwner));
-    if (mruTreeOwner) {
-      nsCOMPtr<nsIBaseWindow> mruBaseWindow(do_QueryInterface(mruTreeOwner));
-      if (mruBaseWindow) {
-        nsCOMPtr<nsIWidget> mruWidget = nullptr;
-        mruBaseWindow->GetMainWidget(getter_AddRefs(mruWidget));
-        if (mruWidget) {
-          *a_nativeWindow = (NSWindow*)mruWidget->GetNativeData(NS_NATIVE_WINDOW);
-        }
-      }
-    }
+  nsPIDOMWindowOuter* win = nsPIDOMWindowOuter::From(a_window);
+  nsCOMPtr<nsIWidget> widget = WidgetUtils::DOMWindowToWidget(win);
+  if (!widget) {
+    return NS_ERROR_FAILURE;
   }
 
+  *a_nativeWindow = (NSWindow*)widget->GetNativeData(NS_NATIVE_WINDOW);
+
   return NS_OK;
 }