Downloads WebUI: fix index out of range when moving focus after remove

Bug: 966300
Change-Id: I4106b1d83ed27574cdb8b6257ffbc9973736634c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1626677Reviewed-by: Hector Carmona <hcarmona@chromium.org>
Commit-Queue: Esmael El-Moslimany <aee@chromium.org>
Cr-Commit-Position: refs/heads/master@{#662895}

chrome/browser/resources/downloads/manager.js

@@ -267,9 +267,10 @@ cr.define('downloads', function() {
                          }]);
       if (this.restoreFocusAfterRemove_) {
         this.restoreFocusAfterRemove_ = false;
-        if (this.items_.length > 0) {
+        const focusIndex = Math.min(this.items_.length - 1, index);
+        if (focusIndex >= 0) {
           setTimeout(() => {
-            this.$.downloadsList.focusItem(index);
+            this.$.downloadsList.focusItem(focusIndex);
             const item = getDeepActiveElement();
             if (item) {
               item.focusOnRemoveButton();