Add method for identifying different InfoBars

chrome/browser/ui/cocoa/keystone_infobar_delegate.mm

Index: chrome/browser/ui/cocoa/keystone_infobar_delegate.mm
diff --git a/chrome/browser/ui/cocoa/keystone_infobar_delegate.mm b/chrome/browser/ui/cocoa/keystone_infobar_delegate.mm
index 24f345a016b79c37f6e610c45d320830d7b0161a..d5e924143155e749cca45a61504e9f385d91fa4a 100644
--- a/chrome/browser/ui/cocoa/keystone_infobar_delegate.mm
+++ b/chrome/browser/ui/cocoa/keystone_infobar_delegate.mm
@@ -51,6 +51,7 @@ class KeystonePromotionInfoBarDelegate : public ConfirmInfoBarDelegate {
   void SetCanExpire() { can_expire_ = true; }
 
   // ConfirmInfoBarDelegate
+  std::string GetIdentifier() const override;
   int GetIconId() const override;
   bool ShouldExpire(const NavigationDetails& details) const override;
   base::string16 GetMessageText() const override;
@@ -104,6 +105,10 @@ KeystonePromotionInfoBarDelegate::KeystonePromotionInfoBarDelegate(
 KeystonePromotionInfoBarDelegate::~KeystonePromotionInfoBarDelegate() {
 }
 
+std::string KeystonePromotionInfoBarDelegate::GetIdentifier() const {
+  return "KeystonePromotionInfoBarDelegate";
+}
+
 int KeystonePromotionInfoBarDelegate::GetIconId() const {
   return IDR_PRODUCT_LOGO_32;
 }