Make menu button take focus from cr-input

CL:1935567 changed the focus behavior to take focus on mousedown if some
other button was currently focussed.

Make the menu button take focus on mousedown for the case where a
<cr-input> element is currently focussed.

Extend unit test to cover the 'cr-input' case.

Bug: 1028461
Tests: browser_test --gtest_filter="*MultiMenu"
Change-Id: I89b067d2eafd547363bbcf289124f0253a87b9c5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1937948
Commit-Queue: Alex Danilo <adanilo@chromium.org>
Reviewed-by: Noel Gordon <noel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#719457}

ui/file_manager/file_manager/foreground/js/ui/multi_menu.js

@@ -322,9 +322,10 @@ cr.define('cr.ui', () => {
                                          // mouse button.
               this.showMenu(false, {x: e.screenX, y: e.screenY});
               // Prevent the button from stealing focus on mousedown unless
-              // focus is on another button.
+              // focus is on another button or cr-input element.
               if (!(document.hasFocus() &&
-                    document.activeElement.tagName === 'BUTTON')) {
+                    (document.activeElement.tagName === 'BUTTON' ||
+                     document.activeElement.tagName === 'CR-INPUT'))) {
                 e.preventDefault();
               }
             }

ui/file_manager/file_manager/foreground/js/ui/multi_menu_unittest.js

@@ -49,6 +49,8 @@ function setUp() {
     '</cr-menu>',
     '<div id="focus-div" tabindex="1"/>',
     '<button id="focus-button" tabindex="2"/>',
+    '<cr-input id="focus-input" tabindex="3">',
+    '</cr-input>',
   ].join('');
 
   // Initialize cr.ui.Command with the <command>s.
@@ -393,4 +395,18 @@ function testFocusMenuButtonWithMouse() {
 
   // Verify the menu button has taken focus.
   assertTrue(document.hasFocus() && document.activeElement === menubutton);
+
+  // Set focus on a cr-input element.
+  //* @type {HTMLElement} */
+  const inputElement = document.querySelector('#focus-input');
+  inputElement.focus();
+
+  // Send mousedown event to the menu button.
+  sendMouseDown('#test-menu-button');
+
+  // Verify the cr-input element has lost focus.
+  assertFalse(document.hasFocus() && document.activeElement === inputElement);
+
+  // Verify the menu button has taken focus.
+  assertTrue(document.hasFocus() && document.activeElement === menubutton);
 }