--- a/.eslintignore
+++ b/.eslintignore
@@ -64,16 +64,18 @@ browser/base/content/test/general/file_c
 browser/base/content/test/urlbar/file_blank_but_not_blank.html
 browser/base/content/newtab/**
 browser/components/downloads/**
 browser/components/feeds/**
 browser/components/privatebrowsing/**
 browser/components/sessionstore/**
 browser/components/tabview/**
 browser/components/translation/**
+# generated files in cld2
+browser/components/translation/cld2/cld-worker.js
 browser/extensions/pdfjs/**
 # generated or library files in pocket
 browser/extensions/pocket/content/panels/js/tmpl.js
 browser/extensions/pocket/content/panels/js/vendor/**
 browser/locales/**
 
 # devtools/ exclusions
 devtools/client/canvasdebugger/**

--- a/browser/components/downloads/test/browser/head.js
+++ b/browser/components/downloads/test/browser/head.js
@@ -136,17 +136,17 @@ function promisePanelOpened()
     // Defer to the next tick of the event loop so that we don't continue
     // processing during the DOM event handler itself.
     setTimeout(deferred.resolve, 0);
   };
 
   return deferred.promise;
 }
 
-function task_resetState()
+function* task_resetState()
 {
   // Remove all downloads.
   let publicList = yield Downloads.getList(Downloads.PUBLIC);
   let downloads = yield publicList.getAll();
   for (let download of downloads) {
     publicList.remove(download);
     yield download.finalize(true);
   }
@@ -180,26 +180,26 @@ function* task_addDownloads(aItems)
     // `"errorObj" in download` must be false when there's no error.
     if (item.errorObj) {
       download.errorObj = item.errorObj;
     }
     yield publicList.add(yield Downloads.createDownload(download));
   }
 }
 
-function task_openPanel()
+function* task_openPanel()
 {
   yield promiseFocus();
 
   let promise = promisePanelOpened();
   DownloadsPanel.showPanel();
   yield promise;
 }
 
-function setDownloadDir() {
+function* setDownloadDir() {
   let tmpDir = Services.dirsvc.get("TmpD", Ci.nsIFile);
   tmpDir.append("testsavedir");
   if (!tmpDir.exists()) {
     tmpDir.create(Ci.nsIFile.DIRECTORY_TYPE, 0o755);
     registerCleanupFunction(function () {
       try {
         tmpDir.remove(true);
       } catch (e) {

--- a/browser/components/sessionstore/test/head.js
+++ b/browser/components/sessionstore/test/head.js
@@ -268,19 +268,21 @@ function promiseRecoveryFileContents() {
   });
 }
 
 var promiseForEachSessionRestoreFile = Task.async(function*(cb) {
   for (let key of SessionFile.Paths.loadOrder) {
     let data = "";
     try {
       data = yield OS.File.read(SessionFile.Paths[key], { encoding: "utf-8" });
-    } catch (ex if ex instanceof OS.File.Error
-	     && ex.becauseNoSuchFile) {
+    } catch (ex) {
       // Ignore missing files
+      if (!(ex instanceof OS.File.Error && ex.becauseNoSuchFile)) {
+        throw ex;
+      }
     }
     cb(data, key);
   }
 });
 
 function promiseBrowserLoaded(aBrowser, ignoreSubFrames = true) {
   return BrowserTestUtils.browserLoaded(aBrowser, !ignoreSubFrames);
 }
@@ -297,17 +299,17 @@ function promiseWindowLoaded(aWindow) {
   return new Promise(resolve => whenWindowLoaded(aWindow, resolve));
 }
 
 var gUniqueCounter = 0;
 function r() {
   return Date.now() + "-" + (++gUniqueCounter);
 }
 
-function BrowserWindowIterator() {
+function* BrowserWindowIterator() {
   let windowsEnum = Services.wm.getEnumerator("navigator:browser");
   while (windowsEnum.hasMoreElements()) {
     let currentWindow = windowsEnum.getNext();
     if (!currentWindow.closed) {
       yield currentWindow;
     }
   }
 }
@@ -367,17 +369,17 @@ var gProgressListener = {
       let args = [browser].concat(gProgressListener._countTabs());
       gProgressListener._callback.apply(gProgressListener, args);
     }
   },
 
   _countTabs: function () {
     let needsRestore = 0, isRestoring = 0, wasRestored = 0;
 
-    for (let win in BrowserWindowIterator()) {
+    for (let win of BrowserWindowIterator()) {
       for (let i = 0; i < win.gBrowser.tabs.length; i++) {
         let browser = win.gBrowser.tabs[i].linkedBrowser;
         if (!browser.__SS_restoreState)
           wasRestored++;
         else if (browser.__SS_restoreState == TAB_STATE_RESTORING)
           isRestoring++;
         else if (browser.__SS_restoreState == TAB_STATE_NEEDS_RESTORE)
           needsRestore++;
@@ -389,17 +391,17 @@ var gProgressListener = {
 
 registerCleanupFunction(function () {
   gProgressListener.unsetCallback();
 });
 
 // Close all but our primary window.
 function promiseAllButPrimaryWindowClosed() {
   let windows = [];
-  for (let win in BrowserWindowIterator()) {
+  for (let win of BrowserWindowIterator()) {
     if (win != window) {
       windows.push(win);
     }
   }
 
   return Promise.all(windows.map(BrowserTestUtils.closeWindow));
 }