Add ContentSuggestionsService

components/ntp_snippets/content_suggestions_category.h

Index: components/ntp_snippets/content_suggestions_category.h
diff --git a/components/ntp_snippets/content_suggestions_category.h b/components/ntp_snippets/content_suggestions_category.h
new file mode 100644
index 0000000000000000000000000000000000000000..98f9a16126861edca586f8f697152e62a703eabf
--- /dev/null
+++ b/components/ntp_snippets/content_suggestions_category.h
@@ -0,0 +1,15 @@
+// Copyright 2016 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.
+
+#ifndef COMPONENTS_NTP_SNIPPETS_CONTENT_SUGGESTIONS_CATEGORY_H_
+#define COMPONENTS_NTP_SNIPPETS_CONTENT_SUGGESTIONS_CATEGORY_H_
+
+namespace ntp_snippets {
+
+// A category groups ContentSuggestions which belong together.
+enum class ContentSuggestionsCategory { ARTICLES, COUNT };
+
+}  // namespace ntp_snippets
+
+#endif  // COMPONENTS_NTP_SNIPPETS_CONTENT_SUGGESTIONS_CATEGORY_H_