Don't deref stale AutofillMetrics pointer in AutofillCCInfoBarDelegate

chrome/browser/autofill/autofill_cc_infobar_delegate.h

Index: chrome/browser/autofill/autofill_cc_infobar_delegate.h
diff --git a/chrome/browser/autofill/autofill_cc_infobar_delegate.h b/chrome/browser/autofill/autofill_cc_infobar_delegate.h
index 2fd4e799708ed9a047d277f78b0d16221bca1729..f7b46f3167de0728c5825bd6e74a96ea6ccdf6e8 100644
--- a/chrome/browser/autofill/autofill_cc_infobar_delegate.h
+++ b/chrome/browser/autofill/autofill_cc_infobar_delegate.h
@@ -44,8 +44,6 @@ class AutofillCCInfoBarDelegate : public ConfirmInfoBarDelegate {
                             const base::Closure& save_card_callback);
   ~AutofillCCInfoBarDelegate() override;
 
-  void LogUserAction(AutofillMetrics::InfoBarMetric user_action);
-
   // ConfirmInfoBarDelegate:
   void InfoBarDismissed() override;
   int GetIconID() const override;
@@ -60,6 +58,7 @@ class AutofillCCInfoBarDelegate : public ConfirmInfoBarDelegate {
 
   // For logging UMA metrics.
   // Weak reference. Owned by the AutofillManager that initiated this infobar.
+  // May be stale during shutdown!
   const AutofillMetrics* metric_logger_;
 
   // The callback to save credit card if the user accepts the infobar.