[Autofill] Add user actions for checkout flow.

components/autofill/core/browser/personal_data_manager.cc

Index: components/autofill/core/browser/personal_data_manager.cc
diff --git a/components/autofill/core/browser/personal_data_manager.cc b/components/autofill/core/browser/personal_data_manager.cc
index 2de59f64c274f807f7b877e4426c5228c8e045f2..18c893933d6e2b6f5b0422855b60426bfc2efaa6 100644
--- a/components/autofill/core/browser/personal_data_manager.cc
+++ b/components/autofill/core/browser/personal_data_manager.cc
@@ -13,6 +13,7 @@
 
 #include "base/i18n/case_conversion.h"
 #include "base/i18n/timezone.h"
+#include "base/metrics/user_metrics.h"
 #include "base/profiler/scoped_tracker.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
@@ -681,6 +682,9 @@ std::vector<Suggestion> PersonalDataManager::GetProfileSuggestions(
   if (IsInAutofillSuggestionsDisabledExperiment())
     return std::vector<Suggestion>();
 
+  base::RecordAction(
+      base::UserMetricsAction("Autofill_PolledProfileSuggestions"));

[Mathieu, 2016/04/11 16:45:46]

would prefer a static method into AutofillMetrics

[sebsg, 2016/04/12 14:40:59]

Done.

+
   base::string16 field_contents_canon =
       AutofillProfile::CanonicalizeProfileString(field_contents);
 
@@ -783,6 +787,9 @@ std::vector<Suggestion> PersonalDataManager::GetCreditCardSuggestions(
   if (IsInAutofillSuggestionsDisabledExperiment())
     return std::vector<Suggestion>();
 
+  base::RecordAction(
+      base::UserMetricsAction("Autofill_PolledCreditCardSuggestions"));
+
   std::list<const CreditCard*> cards_to_suggest;
   std::list<const CreditCard*> substring_matched_cards;
   base::string16 field_contents_lower = base::i18n::ToLower(field_contents);