[NTP::SectionOrder] Add EM oriented order.

chrome/browser/about_flags.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/about_flags.h"
 
 #include <iterator>
 #include <map>
 #include <set>
 #include <utility>
@@ skipping 481 matching lines @@
      "disabled"},
     {IDS_FLAGS_NTP_SWITCH_TO_EXISTING_TAB_MATCH_URL,
      switches::kNtpSwitchToExistingTab, "url"},
     {IDS_FLAGS_NTP_SWITCH_TO_EXISTING_TAB_MATCH_HOST,
      switches::kNtpSwitchToExistingTab, "host"},
 };
 #endif  // OS_ANDROID
 
 #if defined(OS_ANDROID)
 const FeatureEntry::FeatureParam
+    kContentSuggestionsCategoryOrderFeatureVariationGeneral[] = {
+        {ntp_snippets::kCategoryOrderParameter,
+         ntp_snippets::kCategoryOrderGeneral},
+};
+
+const FeatureEntry::FeatureParam
+    kContentSuggestionsCategoryOrderFeatureVariationEMOriented[] = {
+        {ntp_snippets::kCategoryOrderParameter,
+         ntp_snippets::kCategoryOrderEmergingMarketsOriented},
+};
+
+const FeatureEntry::FeatureVariation
+    kContentSuggestionsCategoryOrderFeatureVariations[] = {
+        {"(general)", kContentSuggestionsCategoryOrderFeatureVariationGeneral,
+         arraysize(kContentSuggestionsCategoryOrderFeatureVariationGeneral),
+         nullptr},
+        {"(emerging markets oriented)",
+         kContentSuggestionsCategoryOrderFeatureVariationEMOriented,
+         arraysize(kContentSuggestionsCategoryOrderFeatureVariationEMOriented),
+         nullptr}};
+
+const FeatureEntry::FeatureParam
     kContentSuggestionsCategoryRankerFeatureVariationConstant[] = {
         {ntp_snippets::kCategoryRankerParameter,
          ntp_snippets::kCategoryRankerConstantRanker},
 };
 
 const FeatureEntry::FeatureParam
     kContentSuggestionsCategoryRankerFeatureVariationClickBased[] = {
         {ntp_snippets::kCategoryRankerParameter,
          ntp_snippets::kCategoryRankerClickBasedRanker},
 };
@@ skipping 1313 matching lines @@
     {"disable-audio-support-for-desktop-share",
      IDS_FLAG_DISABLE_AUDIO_FOR_DESKTOP_SHARE,
      IDS_FLAG_DISABLE_AUDIO_FOR_DESKTOP_SHARE_DESCRIPTION, kOsAll,
      SINGLE_VALUE_TYPE(switches::kDisableAudioSupportForDesktopShare)},
 #if BUILDFLAG(ENABLE_EXTENSIONS)
     {"tab-for-desktop-share", IDS_FLAG_DISABLE_TAB_FOR_DESKTOP_SHARE,
      IDS_FLAG_DISABLE_TAB_FOR_DESKTOP_SHARE_DESCRIPTION, kOsAll,
      SINGLE_VALUE_TYPE(extensions::switches::kDisableTabForDesktopShare)},
 #endif  // ENABLE_EXTENSIONS
 #if defined(OS_ANDROID)
+    // TODO(vitaliii): Use ntp_snippets::kStudyName as the feature trial.
+    // Currently, only a single FEATURE_WITH_VARIATIONS_VALUE_TYPE can use a
+    // given study name. See crbug.com/690450.
+    {"content-suggestions-category-order",
+     IDS_FLAGS_CONTENT_SUGGESTIONS_CATEGORY_ORDER_NAME,
+     IDS_FLAGS_CONTENT_SUGGESTIONS_CATEGORY_ORDER_DESCRIPTION, kOsAndroid,
+     FEATURE_WITH_VARIATIONS_VALUE_TYPE(
+         ntp_snippets::kCategoryOrder,
+         kContentSuggestionsCategoryOrderFeatureVariations,
+         "content-suggestions-category-order-feature-trial")},
     {"content-suggestions-category-ranker",
      IDS_FLAGS_CONTENT_SUGGESTIONS_CATEGORY_RANKER_NAME,
      IDS_FLAGS_CONTENT_SUGGESTIONS_CATEGORY_RANKER_DESCRIPTION, kOsAndroid,
      FEATURE_WITH_VARIATIONS_VALUE_TYPE(
          ntp_snippets::kCategoryRanker,
          kContentSuggestionsCategoryRankerFeatureVariations,
          ntp_snippets::kStudyName)},
     {"override-ntp-suggestions-source", IDS_FLAGS_OVERRIDE_SNIPPETS_SOURCE_NAME,
      IDS_FLAGS_OVERRIDE_SNIPPETS_SOURCE_DESCRIPTION, kOsAndroid,
      FEATURE_WITH_VARIATIONS_VALUE_TYPE(ntp_snippets::kContentSuggestionsSource,
@@ skipping 592 matching lines @@
 const base::HistogramBase::Sample kBadSwitchFormatHistogramId = 0;
 
 const FeatureEntry* GetFeatureEntries(size_t* count) {
   *count = arraysize(kFeatureEntries);
   return kFeatureEntries;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags