Bug 1664829 - Add nsIProgressEventSink to AppUpdater so that download progress is correctly reported again. r=bytesized

`AppUpdater` just needs to declare that it implements `nsIProgressEventSink`.
`nsIProgressEventSink.onProgress` is the method that's called whenever download
progress is made, and `AppUpdater` implements it, but the caller doesn't call it
because it checks that consumers are `instanceof nsIProgressEventSink`:
https://searchfox.org/mozilla-central/source/toolkit/mozapps/update/UpdateService.jsm#5014

The legacy aboutDialog updater (which I removed in bug 1600864) has this exact
`generateQI` call, I just forgot to port it over to `AppUpdater`. It also
includes `nsIRequestObserver` since AppUpdater (and the legacy aboutDialog
updater) implements it too.

I've updated all the updater tests (via their head.js) so that they check the
download progress text. This applies to aboutDialog and about:preferences tests.

Differential Revision: https://phabricator.services.mozilla.com/D90632

browser/modules/AppUpdater.jsm

@@ -45,6 +45,10 @@ class AppUpdater {
       "@mozilla.org/updates/update-manager;1",
       "nsIUpdateManager"
     );
+    this.QueryInterface = ChromeUtils.generateQI([
+      "nsIProgressEventSink",
+      "nsIRequestObserver",
+    ]);
   }
 
   /**

toolkit/mozapps/update/tests/browser/head.js

@@ -12,6 +12,11 @@ ChromeUtils.defineModuleGetter(
   "AppMenuNotifications",
   "resource://gre/modules/AppMenuNotifications.jsm"
 );
+ChromeUtils.defineModuleGetter(
+  this,
+  "DownloadUtils",
+  "resource://gre/modules/DownloadUtils.jsm"
+);
 ChromeUtils.defineModuleGetter(
   this,
   "UpdateListener",
@@ -783,6 +788,22 @@ function runAboutDialogUpdateTest(params, steps) {
                 " value should equal " +
                 data[resultName]
             );
+
+            // Check the download status text.  It should be something like,
+            // "1.4 of 1.4 KB".
+            let expectedText = DownloadUtils.getTransferTotal(
+              data[resultName] == gBadSizeResult ? 0 : patch.size,
+              patch.size
+            );
+            Assert.ok(
+              expectedText,
+              "Sanity check: Expected download status text should be non-empty"
+            );
+            Assert.equal(
+              aboutDialog.downloadStatus.textContent,
+              expectedText,
+              "Download status text should be correct"
+            );
           }
         }
       } else if (continueFile) {
@@ -977,6 +998,28 @@ function runAboutPrefsUpdateTest(params, steps) {
                 " value should equal " +
                 data[resultName]
             );
+
+            // Check the download status text.  It should be something like,
+            // "Downloading update — 1.4 of 1.4 KB".  We check only the second
+            // part to make sure that the downloaded size is updated correctly.
+            let actualText = await SpecialPowers.spawn(
+              tab.linkedBrowser,
+              [],
+              () => content.document.getElementById("downloading").textContent
+            );
+            let expectedSuffix = DownloadUtils.getTransferTotal(
+              data[resultName] == gBadSizeResult ? 0 : patch.size,
+              patch.size
+            );
+            Assert.ok(
+              expectedSuffix,
+              "Sanity check: Expected download status text should be non-empty"
+            );
+            Assert.ok(
+              actualText.endsWith(expectedSuffix),
+              "Download status text should end as expected: " +
+                JSON.stringify({ actualText, expectedSuffix })
+            );
           }
         }
       } else if (continueFile) {