Move infobar handling to a tab helper.

chrome/browser/download/download_request_limiter.cc

Index: chrome/browser/download/download_request_limiter.cc
diff --git a/chrome/browser/download/download_request_limiter.cc b/chrome/browser/download/download_request_limiter.cc
index ea9c73ff9b2a34a542771c2714ff2f02e93d1553..011f2c18c4ca150bbc622fc19ccf3bd9c31ad40d 100644
--- a/chrome/browser/download/download_request_limiter.cc
+++ b/chrome/browser/download/download_request_limiter.cc
@@ -6,6 +6,7 @@
 
 #include "base/stl_util.h"
 #include "chrome/browser/download/download_request_infobar_delegate.h"
+#include "chrome/browser/infobars/infobar_tab_helper.h"
 #include "chrome/browser/tab_contents/tab_util.h"
 #include "chrome/browser/ui/tab_contents/tab_contents_wrapper.h"
 #include "content/browser/browser_thread.h"
@@ -76,7 +77,7 @@ void DownloadRequestLimiter::TabDownloadState::PromptUserForDownload(
     infobar_ = new DownloadRequestInfoBarDelegate(tab, this);
     TabContentsWrapper* wrapper =
       TabContentsWrapper::GetCurrentWrapperForContents(tab);
-    wrapper->AddInfoBar(infobar_);
+    wrapper->infobar_tab_helper()->AddInfoBar(infobar_);
   }
 }