Add other variations (with ids) for NTPSnippets to chrome://flags

components/variations/variations_associated_data.h

 // Copyright 2013 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_VARIATIONS_VARIATIONS_ASSOCIATED_DATA_H_
 #define COMPONENTS_VARIATIONS_VARIATIONS_ASSOCIATED_DATA_H_
 
 #include <map>
+#include <memory>
 #include <string>
+#include <vector>
 
 #include "base/metrics/field_trial.h"
 #include "components/variations/active_field_trials.h"
 
 // This file provides various helpers that extend the functionality around
 // base::FieldTrial.
 //
 // This includes several simple APIs to handle getting and setting additional
 // data related to Chrome variations, such as parameters and Google variation
 // IDs. These APIs are meant to extend the base::FieldTrial APIs to offer extra
@@ skipping 21 matching lines @@
 //   // use |id|
 // }
 
 namespace base {
 struct Feature;
 }
 
 namespace variations {
 
 typedef int VariationID;
+class VariationsHttpHeaderProvider;
 
 const VariationID EMPTY_ID = 0;
 
 // A key into the Associate/Get methods for VariationIDs. This is used to create
 // separate ID associations for separate parties interested in VariationIDs.
 enum IDCollectionKey {
   // This collection is used by Google web properties, transmitted through the
   // X-Client-Data header.
   GOOGLE_WEB_PROPERTIES,
   // This collection is used by Google web properties for IDs that trigger
   // server side experimental behavior, transmitted through the
   // X-Client-Data header.
   GOOGLE_WEB_PROPERTIES_TRIGGER,
   // This collection is used by Google update services, transmitted through the
   // Google Update experiment labels.
   GOOGLE_UPDATE_SERVICE,
   // This collection is used by Chrome Sync services, transmitted through the
   // Chrome Sync experiment labels.
   CHROME_SYNC_SERVICE,
   // The total count of collections.
   ID_COLLECTION_COUNT,
 };
 
+// Forces the |variation_ids| (possible extended by |command_line_variation_ids|
+// passed in a command line flag) into a VariationsHttpHeaderProvider that it
+// returns.
+VariationsHttpHeaderProvider* ForceVariationIDsForHttpHeaders(
+    std::vector<std::string> variation_ids,
+    std::string command_line_variation_ids);
+
 // Associate a variations::VariationID value with a FieldTrial group for
 // collection |key|. If an id was previously set for |trial_name| and
 // |group_name|, this does nothing. The group is denoted by |trial_name| and
 // |group_name|. This must be called whenever a FieldTrial is prepared (create
 // the trial and append groups) and needs to have a variations::VariationID
 // associated with it so Google servers can recognize the FieldTrial.
 // Thread safe.
 void AssociateGoogleVariationID(IDCollectionKey key,
                                 const std::string& trial_name,
                                 const std::string& group_name,
@@ skipping 109 matching lines @@
 void ClearAllVariationIDs();
 
 // Clears all of the associated params.
 void ClearAllVariationParams();
 
 }  // namespace testing
 
 }  // namespace variations
 
 #endif  // COMPONENTS_VARIATIONS_VARIATIONS_ASSOCIATED_DATA_H_