Bug 1950734 - Make MSIX builds skip the AUMID altering steps in taskbar pinning as it's unnecessary r=nrishel

Differential Revision: https://phabricator.services.mozilla.com/D239827

browser/components/shell/test/browser.toml

@@ -91,6 +91,9 @@ skip-if = [
 run-if = ["os == 'win'"]
 tags = "os_integration"
 
+["browser_processAUMID.js"]
+run-if = ["os == 'win'"]
+
 ["browser_setDefaultBrowser.js"]
 tags = "os_integration"
 

browser/components/shell/test/browser_processAUMID.js

@@ -0,0 +1,27 @@
+/* Any copyright is dedicated to the Public Domain.
+ * https://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Bug 1950734 tracks how calling PinCurrentAppToTaskbarWin11
+ * on MSIX may cause the process AUMID to be unnecessarily changed.
+ * This test verifies that the behaviour will no longer happen
+ */
+
+ChromeUtils.defineESModuleGetters(this, {
+  ShellService: "resource:///modules/ShellService.sys.mjs",
+});
+
+add_task(async function test_processAUMID() {
+  let processAUMID = ShellService.checkCurrentProcessAUMIDForTesting();
+
+  // This function will trigger the relevant code paths that
+  // incorrectly changes the process AUMID on MSIX, prior to
+  // Bug 1950734 being fixed
+  await ShellService.checkPinCurrentAppToTaskbarAsync(false);
+
+  is(
+    processAUMID,
+    ShellService.checkCurrentProcessAUMIDForTesting(),
+    "The process AUMID should not be changed"
+  );
+});