Bug 907062, resolve the promise if the popup is already open so that the test doesn't occasionally fail, r=paolo

browser/components/downloads/content/downloads.js

@@ -191,12 +191,19 @@ const DownloadsPanel = {
   //// Panel interface
 
   /**
-   * Main panel element in the browser window.
+   * Main panel element in the browser window, or null if the panel overlay
+   * hasn't been loaded yet.
    */
   get panel()
   {
+    // If the downloads panel overlay hasn't loaded yet, just return null
+    // without reseting this.panel.
+    let downloadsPanel = document.getElementById("downloadsPanel");
+    if (!downloadsPanel)
+      return null;
+
     delete this.panel;
-    return this.panel = document.getElementById("downloadsPanel");
+    return this.panel = downloadsPanel;
   },
 
   /**

browser/components/downloads/test/browser/browser_basic_functionality.js

@@ -19,6 +19,9 @@ function test_task()
   ];
 
   try {
+    // Wait for focus first
+    yield promiseFocus();
+
     // Ensure that state is reset in case previous tests didn't finish.
     yield task_resetState();
 

browser/components/downloads/test/browser/browser_first_download_panel.js

@@ -10,6 +10,14 @@
  */
 function test_task()
 {
+  // Clear the download panel has shown preference first as this test is used to
+  // verify this preference's behaviour.
+  let oldPrefValue = true;
+  try {
+    oldPrefValue = Services.prefs.getBoolPref("browser.download.panel.shown");
+  } catch(ex) { }
+  Services.prefs.setBoolPref("browser.download.panel.shown", false);
+
   try {
     // Ensure that state is reset in case previous tests didn't finish.
     yield task_resetState();
@@ -49,5 +57,9 @@ function test_task()
   } finally {
     // Clean up when the test finishes.
     yield task_resetState();
+    // Set the preference instead of clearing it afterwards to ensure the
+    // right value is used no matter what the default was. This ensures the
+    // panel doesn't appear and affect other tests.
+    Services.prefs.setBoolPref("browser.download.panel.shown", oldPrefValue);
   }
 }

browser/components/downloads/test/browser/head.js

@@ -51,6 +51,10 @@ function promisePanelOpened()
 {
   let deferred = Promise.defer();
 
+  if (DownloadsPanel.panel && DownloadsPanel.panel.state == "open") {
+    return deferred.resolve();
+  }
+
   // Hook to wait until the panel is shown.
   let originalOnPopupShown = DownloadsPanel.onPopupShown;
   DownloadsPanel.onPopupShown = function () {
@@ -75,9 +79,6 @@ function task_resetState()
     yield download.finalize(true);
   }
 
-  // Reset any prefs that might have been changed.
-  Services.prefs.clearUserPref("browser.download.panel.shown");
-
   DownloadsPanel.hidePanel();
 
   yield promiseFocus();

testing/profiles/prefs_general.js

@@ -148,3 +148,7 @@ user_pref("geo.provider.testing", true);
 // Background thumbnails in particular cause grief, and disabling thumbnails
 // in general can't hurt - we re-enable them when tests need them.
 user_pref("browser.pagethumbnails.capturing_disabled", true);
+
+// Indicate that the download panel has been shown once so that whichever
+// download test runs first doesn't show the popup inconsistently.
+user_pref("browser.download.panel.shown", true);