Move variations component code to variations namespace.

components/variations/variations_http_header_provider.h

Index: components/variations/variations_http_header_provider.h
===================================================================
--- components/variations/variations_http_header_provider.h	(revision 285608)
+++ components/variations/variations_http_header_provider.h	(working copy)
@@ -96,12 +96,12 @@
 
   // Keep a cache of variation IDs that are transmitted in headers to Google.
   // This consists of a list of valid IDs, and the actual transmitted header.
-  std::set<chrome_variations::VariationID> variation_ids_set_;
-  std::set<chrome_variations::VariationID> variation_trigger_ids_set_;
+  std::set<VariationID> variation_ids_set_;
+  std::set<VariationID> variation_trigger_ids_set_;
 
   // Provides the google experiment ids forced from command line.
-  std::set<chrome_variations::VariationID> default_variation_ids_set_;
-  std::set<chrome_variations::VariationID> default_trigger_id_set_;
+  std::set<VariationID> default_variation_ids_set_;
+  std::set<VariationID> default_trigger_id_set_;
 
   std::string variation_ids_header_;