Chrome Empties: Use Subheadline font in Recently Closed section

The font was previously changed in all illustrated empty states. The font change was also needed in Recent Tabs > Recently Closed.

Because the TableViewDetailTextItem is used in multiple places in Bling, the font had to be changed only in Recent Tabs.

Bug: 1098328
Change-Id: I047f7f53ed1d118a1efd7e3bda9671a8e482630b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2342313Reviewed-by: Sebastien Lalancette <seblalancette@chromium.org>
Reviewed-by: Tommy Martino <tmartino@chromium.org>
Reviewed-by: Sergio Collazos <sczs@chromium.org>
Commit-Queue: Maxime Charland <mcharland@google.com>
Cr-Commit-Position: refs/heads/master@{#795947}

ios/chrome/browser/ui/recent_tabs/recent_tabs_table_view_controller.mm

@@ -840,6 +840,8 @@ const int kRecentlyClosedTabsSectionIndex = 0;
     TableViewDetailTextCell* textCell =
         base::mac::ObjCCastStrict<TableViewDetailTextCell>(cell);
     textCell.detailTextLabel.numberOfLines = 0;
+    textCell.detailTextLabel.font =
+        [UIFont preferredFontForTextStyle:UIFontTextStyleSubheadline];
     textCell.selectionStyle = UITableViewCellSelectionStyleNone;
     textCell.separatorInset =
         UIEdgeInsetsMake(0, tableView.bounds.size.width, 0, 0);