[cleanup] Remove incorrectly overridden focus() method.

The `Button` component didn't override `focus()` correctly, as it wasn't
accepting (and passing through) the `FocusOptions`. It's also
unnecessary to even override the `focus()` method, since we pass
`delegatesFocus: true` when creating the shadow root.

Bug: 301364727
Change-Id: I946204ae086ee6344b099f332da065eb401abafe
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/6179965
Reviewed-by: Alex Rudenko <[email protected]>
Commit-Queue: Benedikt Meurer <[email protected]>
Auto-Submit: Benedikt Meurer <[email protected]>

front_end/ui/components/buttons/Button.test.ts

@@ -54,6 +54,26 @@ describe('Button', () => {
     assert.isTrue(button.disabled);
   });
 
+  describe('focus', () => {
+    it('correctly focuses the <button> element in the shadow DOM', () => {
+      const button = renderButton();
+
+      button.focus();
+
+      assert.isTrue(button.shadowRoot!.querySelector('button')!.hasFocus());
+    });
+  });
+
+  describe('hasFocus', () => {
+    it('correctly reflects the focus state of the button', () => {
+      const button = renderButton();
+
+      button.focus();
+
+      assert.isTrue(button.hasFocus());
+    });
+  });
+
   it('primary button can be clicked', () => {
     testClick({
       variant: Buttons.Button.Variant.PRIMARY,

front_end/ui/components/buttons/Button.ts

@@ -271,10 +271,6 @@ export class Button extends HTMLElement {
     this.#render();
   }
 
-  override focus(): void {
-    this.#shadow.querySelector('button')?.focus();
-  }
-
   connectedCallback(): void {
     this.#render();
   }