Record InstantExtended pref setting on startup with an UMA histogram.

chrome/browser/ui/browser_instant_controller.cc

Index: chrome/browser/ui/browser_instant_controller.cc
===================================================================
--- chrome/browser/ui/browser_instant_controller.cc	(revision 185538)
+++ chrome/browser/ui/browser_instant_controller.cc	(working copy)
@@ -39,6 +39,14 @@
       prefs::kInstantExtendedEnabled : prefs::kInstantEnabled;
 }
 
+// Returns the PrefsService to use for checking the Instant pref for the given
+// profile, or NULL if profile does not support instant.
+PrefService* GetPrefsForInstantEnabledCheck(Profile* profile) {
+  if (profile && !profile->IsOffTheRecord())
+    return profile->GetPrefs();
+  return NULL;
+}
+
 }  // namespace
 
 namespace chrome {
@@ -64,6 +72,15 @@
   ResetInstant();
   browser_->search_model()->AddObserver(this);
 
+  if (chrome::search::IsInstantExtendedAPIEnabled(profile())) {
+    // Only record this for valid (e.g. non-incognito) profiles.
+    PrefService* prefs = GetPrefsForInstantEnabledCheck(profile());
+    if (prefs) {
+      const bool pref_value = prefs->GetBoolean(GetInstantPrefName(profile()));
+      chrome::search::RecordInstantExtendedPrefValue(pref_value);
+    }
+  }
+
 #if defined(ENABLE_THEMES)
   // Listen for theme installation.
   registrar_.Add(this, chrome::NOTIFICATION_BROWSER_THEME_CHANGED,
@@ -77,8 +94,8 @@
 }
 
 bool BrowserInstantController::IsInstantEnabled(Profile* profile) {
-  return profile && !profile->IsOffTheRecord() && profile->GetPrefs() &&
-         profile->GetPrefs()->GetBoolean(GetInstantPrefName(profile));
+  PrefService* prefs = GetPrefsForInstantEnabledCheck(profile);
+  return prefs && prefs->GetBoolean(GetInstantPrefName(profile));
 }
 
 void BrowserInstantController::RegisterUserPrefs(