[NTP::SectionOrder] Propagate new order through ContentSuggestionsService.

components/ntp_snippets/category_rankers/fake_category_ranker.h

Index: components/ntp_snippets/category_rankers/fake_category_ranker.h
diff --git a/components/ntp_snippets/category_rankers/fake_category_ranker.h b/components/ntp_snippets/category_rankers/fake_category_ranker.h
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+++ b/components/ntp_snippets/category_rankers/fake_category_ranker.h
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+// 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_CATEGORY_RANKERS_FAKE_CATEGORY_RANKER_H_
+#define COMPONENTS_NTP_SNIPPETS_CATEGORY_RANKERS_FAKE_CATEGORY_RANKER_H_
+
+#include <vector>
+
+#include "base/time/time.h"
+#include "components/ntp_snippets/category.h"
+#include "components/ntp_snippets/category_rankers/category_ranker.h"
+#include "testing/gmock/include/gmock/gmock.h"
+
+namespace ntp_snippets {
+
+class FakeCategoryRanker : public CategoryRanker {
+ public:
+  FakeCategoryRanker();
+  ~FakeCategoryRanker() override;
+
+  void SetOrder(const std::vector<Category>& new_order) {
+    categories_ = new_order;
+  }
+
+  // CategoryRanker implementation.
+  bool Compare(Category left, Category right) const override;
+  void ClearHistory(base::Time begin, base::Time end) override;
+  void AppendCategoryIfNecessary(Category category) override;
+  void OnSuggestionOpened(Category category) override;
+
+ private:
+  std::vector<Category> categories_;
+};
+
+}  // namespace ntp_snippets
+
+#endif  // COMPONENTS_NTP_SNIPPETS_CATEGORY_RANKERS_FAKE_CATEGORY_RANKER_H_