Add method for identifying different InfoBars

components/infobars/core/infobar_delegate.h

Index: components/infobars/core/infobar_delegate.h
diff --git a/components/infobars/core/infobar_delegate.h b/components/infobars/core/infobar_delegate.h
index bed797f461274d2990cb5e3fe4679f14cd21b819..7c4938169fce8f86c50bd242dc3d94381e3c00fd 100644
--- a/components/infobars/core/infobar_delegate.h
+++ b/components/infobars/core/infobar_delegate.h
@@ -83,6 +83,11 @@ class InfoBarDelegate {
   // as background color) of the infobar.
   virtual Type GetInfoBarType() const;
 
+  // Returns a unique string identifying the infobar.
+  // Implementers of this function must add the string to the InfoBarTypes
+  // enum in histograms.xml.
+  virtual std::string GetIdentifier() const = 0;
+
   virtual InfoBarAutomationType GetInfoBarAutomationType() const;
 
   // Returns the resource ID of the icon to be shown for this InfoBar.  If the