Bug 1677625 - Fix the What's New panel DevTools control buttons. r=emcminn

This was originally fixed in bug 1673733, but then re-broken with a refactor
for unit tests in bug 1673109.

Differential Revision: https://phabricator.services.mozilla.com/D97231

browser/components/newtab/lib/ASRouter.jsm

@@ -1843,29 +1843,27 @@ class _ASRouter {
     );
   }
 
-  async forceWNPanel(browserWindow) {
+  async forceWNPanel(browser) {
+    let win = browser.ownerGlobal;
     await ToolbarPanelHub.enableToolbarButton();
 
-    browserWindow.PanelUI.showSubView(
+    win.PanelUI.showSubView(
       "PanelUI-whatsNew",
-      browserWindow.document.getElementById("whats-new-menu-button")
+      win.document.getElementById("whats-new-menu-button")
     );
 
-    let panel = browserWindow.document.getElementById(
-      "customizationui-widget-panel"
-    );
+    let panel = win.document.getElementById("customizationui-widget-panel");
     // Set the attribute to keep the panel open
     panel.setAttribute("noautohide", true);
   }
 
-  async closeWNPanel(browserWindow) {
-    let panel = browserWindow.document.getElementById(
-      "customizationui-widget-panel"
-    );
+  async closeWNPanel(browser) {
+    let win = browser.ownerGlobal;
+    let panel = win.document.getElementById("customizationui-widget-panel");
     // Set the attribute to allow the panel to close
     panel.setAttribute("noautohide", false);
     // Removing the button is enough to close the panel.
-    await ToolbarPanelHub._hideToolbarButton(browserWindow);
+    await ToolbarPanelHub._hideToolbarButton(win);
   }
 }
 this._ASRouter = _ASRouter;

browser/components/newtab/test/unit/asrouter/ASRouter.test.js

@@ -2207,24 +2207,28 @@ describe("ASRouter", () => {
   });
 
   describe("#forceWNPanel", () => {
-    let browserWindow = {
-      document: new Document(),
-      PanelUI: {
-        showSubView: sinon.stub(),
-        panel: {
-          setAttribute: sinon.stub(),
+    let browser = {
+      ownerGlobal: {
+        document: new Document(),
+        PanelUI: {
+          showSubView: sinon.stub(),
+          panel: {
+            setAttribute: sinon.stub(),
+          },
         },
       },
     };
     let fakePanel = {
       setAttribute: sinon.stub(),
     };
-    sinon.stub(browserWindow.document, "getElementById").returns(fakePanel);
+    sinon
+      .stub(browser.ownerGlobal.document, "getElementById")
+      .returns(fakePanel);
 
     it("should call enableToolbarButton", async () => {
-      await Router.forceWNPanel(browserWindow);
+      await Router.forceWNPanel(browser);
       assert.calledOnce(FakeToolbarPanelHub.enableToolbarButton);
-      assert.calledOnce(browserWindow.PanelUI.showSubView);
+      assert.calledOnce(browser.ownerGlobal.PanelUI.showSubView);
       assert.calledWith(fakePanel.setAttribute, "noautohide", true);
     });
   });