Add method for identifying different InfoBars

chrome/browser/ui/cocoa/infobars/mock_confirm_infobar_delegate.cc

Index: chrome/browser/ui/cocoa/infobars/mock_confirm_infobar_delegate.cc
diff --git a/chrome/browser/ui/cocoa/infobars/mock_confirm_infobar_delegate.cc b/chrome/browser/ui/cocoa/infobars/mock_confirm_infobar_delegate.cc
index c94b2e9a05f029c0430680f7183920a4b80a4d38..620f5e8ec5e4e92587c8270e5330701af072a559 100644
--- a/chrome/browser/ui/cocoa/infobars/mock_confirm_infobar_delegate.cc
+++ b/chrome/browser/ui/cocoa/infobars/mock_confirm_infobar_delegate.cc
@@ -25,6 +25,11 @@ MockConfirmInfoBarDelegate::~MockConfirmInfoBarDelegate() {
     owner_->OnInfoBarDelegateClosed(this);
 }
 
+infobars::InfoBarDelegate::InfoBarIdentifier
+MockConfirmInfoBarDelegate::GetIdentifier() const {
+  return TEST_INFOBAR_ID;
+}
+
 int MockConfirmInfoBarDelegate::GetIconId() const {
   icon_accessed_ = true;
   return kNoIconID;