Resetting metrics ids on clump detection.

chrome/browser/metrics/metrics_service.cc

Index: chrome/browser/metrics/metrics_service.cc
diff --git a/chrome/browser/metrics/metrics_service.cc b/chrome/browser/metrics/metrics_service.cc
index a313c4514051b636009db4616c10559f98a64ca5..0360d7c1556c8b2a6d485d7eb770aecbf4f98025 100644
--- a/chrome/browser/metrics/metrics_service.cc
+++ b/chrome/browser/metrics/metrics_service.cc
@@ -163,6 +163,8 @@
 
 #include "chrome/browser/metrics/metrics_service.h"
 
+#include "base/debug/stack_trace.h"
+
 #include <algorithm>
 
 #include "base/bind.h"
@@ -631,8 +633,12 @@ MetricsService::CreateEntropyProvider(ReportingState reporting_state) {
 }
 
 void MetricsService::ForceClientIdCreation() {
+  DVLOG(2) << "\n\nCreating client id\n\n";
+  base::debug::StackTrace st;
+  // DVLOG(2) << st.ToString();
   if (!client_id_.empty())
     return;
+  DVLOG(2) << "\n\nActually creating id\n\n";
   PrefService* pref = g_browser_process->local_state();
   client_id_ = pref->GetString(prefs::kMetricsClientID);
   if (!client_id_.empty())
@@ -1186,6 +1192,9 @@ void MetricsService::GetUptimes(PrefService* pref,
 }
 
 int MetricsService::GetLowEntropySource() {
+  DVLOG(2) << "\n\nGetting LES\n\n";
+  base::debug::StackTrace st;
+  // DVLOG(2) << st.ToString();
   // Note that the default value for the low entropy source and the default pref
   // value are both kLowEntropySourceNotSet, which is used to identify if the
   // value has been set or not.
@@ -1862,6 +1871,7 @@ void MetricsService::RegisterSyntheticFieldTrial(
 }
 
 void MetricsService::CheckForClonedInstall() {
+  DVLOG(2) << "\n\nChecking for cloned installs\n\n";
   DCHECK(!cloned_install_detector_);
 
   metrics::MachineIdProvider* provider =
@@ -1876,6 +1886,19 @@ void MetricsService::CheckForClonedInstall() {
   cloned_install_detector_->CheckForClonedInstall(local_state);
 }
 
+void MetricsService::ResetVariationsState() {
+  PrefService* local_state = g_browser_process->local_state();
+  DCHECK(local_state->GetBoolean(prefs::kMetricsCloneDetected));
+  DCHECK(client_id_.empty());
+  DCHECK(low_entropy_source_ == kLowEntropySourceNotSet);
+
+  DVLOG(2) << "\n\nresetting variatinos state\n\n";
+
+  local_state->ClearPref(prefs::kMetricsClientID);
+  local_state->ClearPref(prefs::kMetricsLowEntropySource);
+  local_state->SetBoolean(prefs::kMetricsCloneDetected, false);

[Alexei Svitkine (slow), 2014/03/26 21:34:50]

Why not ClearPref()?

[jwd, 2014/03/28 16:23:49]

Done.

+}
+
 void MetricsService::GetCurrentSyntheticFieldTrials(
     std::vector<chrome_variations::ActiveGroupId>* synthetic_trials) {
   DCHECK(synthetic_trials);