Remove outdated April fool joke.

src/sidebar/media-embedder.js

@@ -105,10 +105,6 @@ function youTubeQueryParams(link) {
  * Return a YouTube embed (<iframe>) DOM element for the given video ID.
  */
 function youTubeEmbed(id, link) {
-  const now = new Date();
-  if (now.getFullYear() === 2018 && now.getMonth() === 3 && now.getDate() === 1) {
-    id = 'dQw4w9WgXcQ';
-  }
   const query  = youTubeQueryParams(link);
   return iframe(`https://www.youtube.com/embed/${id}${query}`);
 }

src/sidebar/test/media-embedder-test.js

@@ -362,15 +362,4 @@ describe('media-embedder', function () {
     assert.equal(
       element.children[1].src, 'https://www.youtube.com/embed/abcdefg');
   });
-
-  it('never gives you up', () => {
-    var url = 'https://www.youtube.com/watch?v=deadbeef';
-    var element = domElement(`<a href="${url}">${url}</a>`);
-
-    clock.tick(new Date('2018-04-01').getTime());
-    mediaEmbedder.replaceLinksWithEmbeds(element);
-
-    assert.equal(element.children[0].tagName, 'IFRAME');
-    assert.equal(element.children[0].src, 'https://www.youtube.com/embed/dQw4w9WgXcQ');
-  });
 });