[Explore sites] Add new feature parameter for personalization

Bug: 918436
Change-Id: I5311199b6dff15400d36308c35dbf7aa9469be98
Reviewed-on: https://chromium-review.googlesource.com/c/1392501
Commit-Queue: Cathy Li <chili@chromium.org>
Reviewed-by: Justin DeWitt <dewittj@chromium.org>
Reviewed-by: Theresa <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#619707}

chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageLayout.java

@@ -238,12 +238,20 @@ public class NewTabPageLayout extends LinearLayout implements TileGroup.Observer
         mSiteSectionViewHolder = SiteSection.createViewHolder(getSiteSectionView(), mUiConfig);
         mSiteSectionViewHolder.bindDataSource(mTileGroup, tileRenderer);
 
-        if (ExploreSitesBridge.getVariation() == ExploreSitesVariation.ENABLED) {
-            mExploreSection = new ExploreSitesSection(mExploreSectionView, profile,
-                    mManager.getNavigationDelegate(), SuggestionsConfig.getTileStyle(mUiConfig));
-        } else if (ExploreSitesBridge.getVariation() == ExploreSitesVariation.EXPERIMENT) {
-            mExploreSection = new ExperimentalExploreSitesSection(
-                    mExploreSectionView, profile, mManager.getNavigationDelegate());
+        int variation = ExploreSitesBridge.getVariation();
+        switch (variation) {
+            case ExploreSitesVariation.ENABLED: // fall-through
+            case ExploreSitesVariation.PERSONALIZED:
+                mExploreSection = new ExploreSitesSection(mExploreSectionView, profile,
+                        mManager.getNavigationDelegate(),
+                        SuggestionsConfig.getTileStyle(mUiConfig));
+                break;
+            case ExploreSitesVariation.EXPERIMENT:
+                mExploreSection = new ExperimentalExploreSitesSection(
+                        mExploreSectionView, profile, mManager.getNavigationDelegate());
+                break;
+            case ExploreSitesVariation.DISABLED: // fall-through
+            default: // do nothing.
         }
 
         mSearchProviderLogoView = findViewById(R.id.search_provider_logo);

chrome/browser/about_flags.cc

@@ -1118,8 +1118,12 @@ const FeatureEntry::FeatureVariation kNewNetErrorPageUIVariations[] = {
 const FeatureEntry::FeatureParam kExploreSitesExperimental = {
     chrome::android::explore_sites::kExploreSitesVariationParameterName,
     chrome::android::explore_sites::kExploreSitesVariationExperimental};
+const FeatureEntry::FeatureParam kExploreSitesPersonalized = {
+    chrome::android::explore_sites::kExploreSitesVariationParameterName,
+    chrome::android::explore_sites::kExploreSitesVariationPersonalized};
 const FeatureEntry::FeatureVariation kExploreSitesVariations[] = {
-    {"Experimental", &kExploreSitesExperimental, 1, nullptr}};
+    {"Experimental", &kExploreSitesExperimental, 1, nullptr},
+    {"Personalized", &kExploreSitesPersonalized, 1, nullptr}};
 #endif  // defined(OS_ANDROID)
 
 const FeatureEntry::FeatureParam

chrome/browser/android/explore_sites/explore_sites_feature.cc

@@ -15,6 +15,7 @@ namespace explore_sites {
 const char kExploreSitesVariationParameterName[] = "variation";
 
 const char kExploreSitesVariationExperimental[] = "experiment";
+const char kExploreSitesVariationPersonalized[] = "personalized";
 
 ExploreSitesVariation GetExploreSitesVariation() {
   if (base::FeatureList::IsEnabled(kExploreSites)) {
@@ -23,6 +24,11 @@ ExploreSitesVariation GetExploreSitesVariation() {
         kExploreSitesVariationExperimental) {
       return ExploreSitesVariation::EXPERIMENT;
     }
+    if (base::GetFieldTrialParamValueByFeature(
+            kExploreSites, kExploreSitesVariationParameterName) ==
+        kExploreSitesVariationPersonalized) {
+      return ExploreSitesVariation::PERSONALIZED;
+    }
     return ExploreSitesVariation::ENABLED;
   }
   return ExploreSitesVariation::DISABLED;

chrome/browser/android/explore_sites/explore_sites_feature.h

@@ -12,10 +12,16 @@ namespace explore_sites {
 extern const char kExploreSitesVariationParameterName[];
 
 extern const char kExploreSitesVariationExperimental[];
+extern const char kExploreSitesVariationPersonalized[];
 
 // A Java counterpart will be generated for this enum.
 // GENERATED_JAVA_ENUM_PACKAGE: org.chromium.chrome.browser.explore_sites
-enum class ExploreSitesVariation { ENABLED, EXPERIMENT, DISABLED };
+enum class ExploreSitesVariation {
+  ENABLED,
+  EXPERIMENT,
+  PERSONALIZED,
+  DISABLED
+};
 
 ExploreSitesVariation GetExploreSitesVariation();
 

chrome/browser/ui/webui/explore_sites_internals/explore_sites_internals_page_handler.cc

@@ -26,6 +26,8 @@ std::string GetChromeFlagsSetupString() {
       return "Enabled";
     case ExploreSitesVariation::EXPERIMENT:
       return "Experiment";
+    case ExploreSitesVariation::PERSONALIZED:
+      return "Personalized";
     case ExploreSitesVariation::DISABLED:
       return "Disabled";
   }