Add ContentSuggestion, ContentSuggestionCategory and ContentSuggestionProviderType

components/ntp_snippets/ntp_snippet.cc

Index: components/ntp_snippets/ntp_snippet.cc
diff --git a/components/ntp_snippets/ntp_snippet.cc b/components/ntp_snippets/ntp_snippet.cc
index d7ca20c3392fd76c088a5de45aff7ebf92527627..5e2835e93bbdd433bbabf1ed8103044cb7c6887c 100644
--- a/components/ntp_snippets/ntp_snippet.cc
+++ b/components/ntp_snippets/ntp_snippet.cc
@@ -8,6 +8,9 @@
 #include "base/strings/stringprintf.h"
 #include "base/values.h"
 #include "components/ntp_snippets/proto/ntp_snippets.pb.h"
+#include "components/ntp_snippets/snippet.h"
+#include "components/ntp_snippets/snippet_category.h"
+#include "components/ntp_snippets/snippet_provider_type.h"
 
 namespace {
 
@@ -221,6 +224,19 @@ SnippetProto NTPSnippet::ToProto() const {
   return result;
 }
 
+std::unique_ptr<Snippet> NTPSnippet::ToSnippet() const {
+  std::unique_ptr<Snippet> result(new Snippet(
+      id_, SnippetProviderType::ARTICLES, SnippetCategory::ARTICLE));
+  result->set_url(best_source().url);
+  result->set_amp_url(best_source().amp_url);
+  result->set_title(title_);
+  result->set_text_extract(snippet_);
+  result->set_publish_date(publish_date_);
+  result->set_publisher_name(best_source().publisher_name);
+  result->set_score(score_);
+  return result;
+}
+
 // static
 base::Time NTPSnippet::TimeFromJsonString(const std::string& timestamp_str) {
   int64_t timestamp;