Move active field trial API to variations component.

components/variations/variations_associated_data.cc

Index: components/variations/variations_associated_data.cc
===================================================================
--- components/variations/variations_associated_data.cc	(revision 271393)
+++ components/variations/variations_associated_data.cc	(working copy)
@@ -9,10 +9,14 @@
 #include <vector>
 
 #include "base/memory/singleton.h"
-#include "components/variations/metrics_util.h"
 
 namespace chrome_variations {
 
+// TODO(asvitkine): Delete these when this file moves to variations namespace.
+using variations::ActiveGroupId;
+using variations::ActiveGroupIdCompare;
+using variations::MakeActiveGroupId;
+
 namespace {
 
 // The internal singleton accessor for the map, used to keep it thread-safe.
@@ -173,14 +177,6 @@
 
 }  // namespace
 
-ActiveGroupId MakeActiveGroupId(const std::string& trial_name,
-                                const std::string& group_name) {
-  ActiveGroupId id;
-  id.name = metrics::HashName(trial_name);
-  id.group = metrics::HashName(group_name);
-  return id;
-}
-
 void AssociateGoogleVariationID(IDCollectionKey key,
                                 const std::string& trial_name,
                                 const std::string& group_name,