ambient: Fix topic source row height

The row height should be 64px for two lines Settings.

Bug: b/166807600
Test: new js test
Change-Id: I7a06e51b4d921e55457a5ffbe35964c888c1c979
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2399767Reviewed-by: Jimmy Gong <jimmyxgong@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: Tao Wu <wutao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#806010}

chrome/browser/resources/settings/chromeos/ambient_mode_page/topic_source_list.html

@@ -18,7 +18,7 @@
 
       topic-source-item {
         align-items: center;
-        height: 48px;
+        height: 64px;
       }
 
       iron-list > *:not(:first-of-type) {

chrome/test/data/webui/settings/chromeos/ambient_mode_page_test.js

@@ -147,6 +147,16 @@ suite('AmbientModeHandler', function() {
     assertEquals(2, topicSourceItems.length);
   });
 
+  test('topicSourceItemHasCorrectRowHeight', function() {
+    const topicSourceListElement = ambientModePage.$$('topic-source-list');
+    const ironList = topicSourceListElement.$$('iron-list');
+    const topicSourceItems = ironList.querySelectorAll('topic-source-item');
+
+    topicSourceItems.forEach((row) => {
+      assertEquals(64, row.offsetHeight);
+    });
+  });
+
   test('Deep link to topic sources', async () => {
     loadTimeData.overrideValues({isDeepLinkingEnabled: true});
     assertTrue(loadTimeData.getBoolean('isDeepLinkingEnabled'));