Remove remaining dependencies of infobars on content/.

chrome/browser/infobars/infobar_service.cc

Index: chrome/browser/infobars/infobar_service.cc
diff --git a/chrome/browser/infobars/infobar_service.cc b/chrome/browser/infobars/infobar_service.cc
index a6a7d94b1f5189808bc6cf5291b177ee18878a9e..5b58273d5b6b43c8730b4d0a952b175a4d11a196 100644
--- a/chrome/browser/infobars/infobar_service.cc
+++ b/chrome/browser/infobars/infobar_service.cc
@@ -55,6 +55,12 @@ InfoBarService::~InfoBarService() {
   ShutDown();
 }
 
+int InfoBarService::GetActiveEntryID() {
+  content::NavigationEntry* active_entry =
+      web_contents()->GetController().GetActiveEntry();
+  return active_entry ? active_entry->GetUniqueID() : 0;
+}
+
 void InfoBarService::NotifyInfoBarAdded(InfoBar* infobar) {
   InfoBarManager::NotifyInfoBarAdded(infobar);
   // TODO(droger): Remove the notifications and have listeners change to be