A few small tweaks based on further analysis of GoogleURLTracker:

chrome/browser/infobars/infobar_tab_helper.cc

Index: chrome/browser/infobars/infobar_tab_helper.cc
===================================================================
--- chrome/browser/infobars/infobar_tab_helper.cc	(revision 134398)
+++ chrome/browser/infobars/infobar_tab_helper.cc	(working copy)
@@ -39,7 +39,9 @@
   }
 
   for (size_t i = 0; i < infobars_.size(); ++i) {
-    if (GetInfoBarDelegateAt(i)->EqualsDelegate(delegate)) {
+    InfoBarDelegate* delegate_at_i = GetInfoBarDelegateAt(i);

[Ilya Sherman, 2012/05/02 03:52:43]

nit: Perhaps use an iterator instead of creating this temporary variable (unless
it's important to use GetInfoBarDelegateAt() here)?

+    if (delegate_at_i->EqualsDelegate(delegate)) {
+      DCHECK_NE(delegate_at_i, delegate);
       delegate->InfoBarClosed();
       return;
     }