Track adding a new user automatically.

chrome/browser/profiles/profile_metrics.h

Index: chrome/browser/profiles/profile_metrics.h
diff --git a/chrome/browser/profiles/profile_metrics.h b/chrome/browser/profiles/profile_metrics.h
index ffc59c8418d77170104cd9f787b0bb1194f2f25f..611c62e1cfa048f0b491784ac74c6777591748e7 100644
--- a/chrome/browser/profiles/profile_metrics.h
+++ b/chrome/browser/profiles/profile_metrics.h
@@ -33,10 +33,11 @@ class ProfileMetrics {
 
   // Enum for counting the ways users were added.
   enum ProfileAdd {
-    ADD_NEW_USER_ICON = 0,    // User adds new user from icon menu
-    ADD_NEW_USER_MENU,        // User adds new user from menu bar
-    ADD_NEW_USER_DIALOG,      // User adds new user from create-profile dialog
-    ADD_NEW_USER_MANAGER,     // User adds new user from User Manager
+    ADD_NEW_USER_ICON = 0,      // User adds new user from icon menu
+    ADD_NEW_USER_MENU,          // User adds new user from menu bar
+    ADD_NEW_USER_DIALOG,        // User adds new user from create-profile dialog
+    ADD_NEW_USER_MANAGER,       // User adds new user from User Manager
+    ADD_NEW_USER_LAST_DELETED,  // Auto-created after deleting last user
     NUM_PROFILE_ADD_METRICS
   };