Work around testdriver issue in select-mousedown-slot-mutation

Using test_driver.click() isn't working in chromium for certain
elements, in this case the option element inside the picker. Using
test_driver.Actions() gets around this issue.

Bug: 488072422
Change-Id: I13068c98877473f9e6ef9a5fa22c6cc9c76444a9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7617854
Reviewed-by: Joey Arhar <jarhar@chromium.org>
Reviewed-by: David Grogan <dgrogan@chromium.org>
Commit-Queue: Joey Arhar <jarhar@chromium.org>
Commit-Queue: David Grogan <dgrogan@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1592705}

Author: josepharhar

html/semantics/forms/the-select-element/customizable-select/select-mousedown-slot-mutation.optional.html

@@ -3,6 +3,7 @@
 <script src="/resources/testharnessreport.js"></script>
 <script src="/resources/testdriver.js"></script>
 <script src="/resources/testdriver-vendor.js"></script>
+<script src="/resources/testdriver-actions.js"></script>
 
 <!-- This test verifies that mutating a select's options during mousedown
   does not prevent the picker from opening. This is a regression test for
@@ -22,6 +23,14 @@
 </style>
 
 <script>
+  function click(element) {
+    return (new test_driver.Actions()
+      .pointerMove(0, 0, {origin: element})
+      .pointerDown()
+      .pointerUp())
+      .send();
+  }
+
   const select = document.getElementById('test-select');
 
   // Mutate the select's options on mousedown, similar to what
@@ -58,7 +67,7 @@
     assert_false(select.matches(':open'), 'select should be closed initially');
 
     // Click the select - it should open despite the mousedown mutation
-    await test_driver.click(select);
+    await click(select);
 
     assert_true(select.matches(':open'), 'select should be open after click despite mousedown mutation');
 
@@ -76,12 +85,12 @@
     assert_equals(select.options[2].value, 'c', 'third option should be "c"');
 
     // Click to open
-    await test_driver.click(select);
+    await click(select);
     assert_true(select.matches(':open'), 'select should be open');
 
     // Verify options still work after mutation - click second option
     const option2 = select.options[1];
-    await test_driver.click(option2);
+    await click(option2);
 
     assert_false(select.matches(':open'), 'select should be closed after selection');
     assert_equals(select.value, 'b', 'selected value should be "b"');