Remove the hash fields from FieldTrials.

chrome/browser/metrics/metrics_log.cc

Index: chrome/browser/metrics/metrics_log.cc
diff --git a/chrome/browser/metrics/metrics_log.cc b/chrome/browser/metrics/metrics_log.cc
index 58cdfa1c312eaeb8f63e7538c4ae04dbfbff9814..78b0c54c2b7620206d124bfb375e1cc30ffd0a01 100644
--- a/chrome/browser/metrics/metrics_log.cc
+++ b/chrome/browser/metrics/metrics_log.cc
@@ -26,6 +26,7 @@
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/chrome_version_info.h"
 #include "chrome/common/logging_chrome.h"
+#include "chrome/common/metrics/experiments_helper.h"
 #include "chrome/common/metrics/proto/omnibox_event.pb.h"
 #include "chrome/common/metrics/proto/system_profile.pb.h"
 #include "chrome/common/pref_names.h"
@@ -47,7 +48,7 @@ extern "C" IMAGE_DOS_HEADER __ImageBase;
 using content::GpuDataManager;
 using metrics::OmniboxEventProto;
 using metrics::SystemProfileProto;
-typedef base::FieldTrial::NameGroupId NameGroupId;
+typedef experiments_helper::NameGroupId NameGroupId;
 
 namespace {
 
@@ -274,7 +275,7 @@ int MetricsLog::GetScreenCount() const {
 
 void MetricsLog::GetFieldTrialIds(
     std::vector<NameGroupId>* field_trial_ids) const {
-  base::FieldTrialList::GetFieldTrialNameGroupIds(field_trial_ids);
+  experiments_helper::GetFieldTrialNameGroupIds(field_trial_ids);
 }
 
 void MetricsLog::WriteStabilityElement(