Add header for the Content Suggestions

ios/chrome/browser/ui/content_suggestions/content_suggestions_header_item.mm

Index: ios/chrome/browser/ui/content_suggestions/content_suggestions_header_item.mm
diff --git a/ios/chrome/browser/ui/content_suggestions/content_suggestions_header_item.mm b/ios/chrome/browser/ui/content_suggestions/content_suggestions_header_item.mm
new file mode 100644
index 0000000000000000000000000000000000000000..8cdc5222783353ea079d7e57dc249cc14a340d04
--- /dev/null
+++ b/ios/chrome/browser/ui/content_suggestions/content_suggestions_header_item.mm
@@ -0,0 +1,15 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import "ios/chrome/browser/ui/content_suggestions/content_suggestions_header_item.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+@implementation ContentSuggestionsHeaderItem
+
+@synthesize suggestionIdentifier = _suggestionIdentifier;

[lpromero, 2017/03/16 16:43:21]

Can you add a comment like:

// Do not add more functionality to this class. If needed, please create a new
subclass of CollectionViewItem instead of CollectionViewTextItem.

[gambard, 2017/03/17 09:33:39]

Acknowledged.

+
+@end