Bug 1260535 - Update the UI of the tab when window.open() is executed from a container tab, r=mconley

browser/base/content/tab-content.js

@@ -848,6 +848,28 @@ var RefreshBlocker = {
 
 RefreshBlocker.init();
 
+var UserContextIdNotifier = {
+  init() {
+    addEventListener("DOMContentLoaded", this);
+  },
+
+  uninit() {
+    removeEventListener("DOMContentLoaded", this);
+  },
+
+  handleEvent(aEvent) {
+    // When the first content is loaded, we want to inform the tabbrowser about
+    // the userContextId in use in order to update the UI correctly.
+    // Just because we cannot change the userContextId from an active docShell,
+    // we don't need to check DOMContentLoaded again.
+    this.uninit();
+    let userContextId = content.document.nodePrincipal.originAttributes.userContextId;
+    sendAsyncMessage("Browser:FirstContentLoaded", { userContextId });
+  }
+};
+
+UserContextIdNotifier.init();
+
 ExtensionContent.init(this);
 addEventListener("unload", () => {
   ExtensionContent.uninit(this);

browser/base/content/tabbrowser.xml

@@ -4285,6 +4285,14 @@
               browser.messageManager.sendAsyncMessage("Browser:AppTab", { isAppTab: tab.pinned })
               break;
             }
+            case "Browser:FirstContentLoaded": {
+              let tab = this.getTabForBrowser(browser);
+              if (tab && data.userContextId) {
+                tab.setUserContextId(data.userContextId);
+              }
+
+              break;
+            }
             case "Findbar:Keypress": {
               let tab = this.getTabForBrowser(browser);
               // If the find bar for this tab is not yet alive, only initialize
@@ -4431,6 +4439,7 @@
           messageManager.addMessageListener("DOMWebNotificationClicked", this);
           messageManager.addMessageListener("DOMServiceWorkerFocusClient", this);
           messageManager.addMessageListener("RefreshBlocker:Blocked", this);
+          messageManager.addMessageListener("Browser:FirstContentLoaded", this);
 
           // To correctly handle keypresses for potential FindAsYouType, while
           // the tab's find bar is not yet initialized.

browser/components/contextualidentity/test/browser/browser.ini

@@ -6,3 +6,4 @@ support-files =
 
 [browser_usercontext.js]
 [browser_windowName.js]
+[browser_windowOpen.js]

browser/components/contextualidentity/test/browser/browser_windowOpen.js

@@ -0,0 +1,41 @@
+"use strict";
+
+// Here we want to test that a new opened window shows the same UI of the
+// parent one if this has been loaded from a particular container.
+
+const BASE_URI = "http://mochi.test:8888/browser/browser/components/"
+  + "contextualidentity/test/browser/empty_file.html";
+
+add_task(function* setup() {
+  yield new Promise((resolve) => {
+    SpecialPowers.pushPrefEnv({"set": [
+      ["privacy.userContext.enabled", true],
+      ["browser.link.open_newwindow", 2],
+    ]}, resolve);
+  });
+});
+
+
+add_task(function* test() {
+  info("Creating a tab with UCI = 1...");
+  let tab = gBrowser.addTab(BASE_URI, {userContextId: 1});
+  is(tab.getAttribute('usercontextid'), 1, "New tab has UCI equal 1");
+
+  let browser = gBrowser.getBrowserForTab(tab);
+  yield BrowserTestUtils.browserLoaded(browser);
+
+  info("Opening a new window from this tab...");
+  ContentTask.spawn(browser, BASE_URI, function(url) {
+    content.window.newWindow = content.window.open(url, "_blank");
+  });
+
+  let newWin = yield BrowserTestUtils.waitForNewWindow();
+  let newTab = newWin.gBrowser.selectedTab;
+
+  yield BrowserTestUtils.browserLoaded(newTab.linkedBrowser);
+  is(newTab.getAttribute('usercontextid'), 1, "New tab has UCI equal 1");
+
+  info("Closing the new window and tab...");
+  yield BrowserTestUtils.closeWindow(newWin);
+  yield BrowserTestUtils.removeTab(tab);
+});