fix: Improve test robustness.

Author: BenHenning

test/webdriverio/test/basic_test.ts

@@ -405,8 +405,10 @@ suite('Keyboard navigation on Fields', function () {
     await focusOnBlock(this.browser, 'logic_boolean_1');
     // Select the field.
     await keyRight(this.browser);
-    // Open the field's editor.
+    // Open the field's editor and select the first option to give a child of
+    // the editor focus.
     await sendKeyAndWait(this.browser, Key.Enter);
+    await keyDown(this.browser);
 
     // Exit the editor.
     await sendKeyAndWait(this.browser, Key.Escape);

test/webdriverio/test/test_setup.ts

@@ -398,8 +398,9 @@ export async function getFocusedFieldName(
   browser: WebdriverIO.Browser,
 ): Promise<string | undefined> {
   return await browser.execute(() => {
-    const field = Blockly.getFocusManager().getFocusedNode() as Blockly.Field;
-    return field.name;
+    const field =
+      Blockly.getFocusManager().getFocusedNode() as Blockly.Field | null;
+    return field?.name;
   });
 }