Add a mechanism to force parameters of a group to a specific value.

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 <string>
 
@@ skipping 95 matching lines @@
                                            const ActiveGroupId& active_group);
 
 // Associates the specified set of key-value |params| with the variation
 // specified by |trial_name| and |group_name|. Fails and returns false if the
 // specified variation already has params associated with it or the field trial
 // is already active (group() has been called on it). Thread safe.
 bool AssociateVariationParams(const std::string& trial_name,
                               const std::string& group_name,
                               const std::map<std::string, std::string>& params);
 
+// Provide a mechanism to associate multiple set of params to multiple groups

[Alexei Svitkine (slow), 2015/04/29 15:34:25]

Nit: Provide -> Provides

[danduong, 2015/04/29 21:00:09]

Done.

+// with a formatted string specified from commandline. For example:
+// "trial1.group1:k1/v1/k2/v2,trial2.group2:k1/v1" defines parameters for two
+// variations. One of which is identified with trial name "trial1" and group
+// name "group1". This variation also has two key/value pairs associated in the
+// paramenters (k1,v1 and k2,v2).

[Alexei Svitkine (slow), 2015/04/29 15:34:25]

Mention something about the escape format.

You could also leave this description brief and reference the comment on the
command-line flag declaration.

[danduong, 2015/04/29 21:00:09]

Done.

+bool AssociateParamsFromString(const std::string& variations_string);
+
 // Retrieves the set of key-value |params| for the variation associated with
 // the specified field trial, based on its selected group. If the field trial
 // does not exist or its selected group does not have any parameters associated
 // with it, returns false and does not modify |params|. Calling this function
 // will result in the field trial being marked as active if found (i.e. group()
 // will be called on it), if it wasn't already. Currently, this information is
 // only available from the browser process. Thread safe.
 bool GetVariationParams(const std::string& trial_name,
                         std::map<std::string, std::string>* params);
 
@@ skipping 14 matching lines @@
 void ClearAllVariationIDs();
 
 // Clears all of the associated params.
 void ClearAllVariationParams();
 
 }  // namespace testing
 
 }  // namespace variations
 
 #endif  // COMPONENTS_VARIATIONS_VARIATIONS_ASSOCIATED_DATA_H_