Remove DeleteTask and convert remaining users.

chrome/browser/ui/webui/chrome_url_data_manager.h

Index: chrome/browser/ui/webui/chrome_url_data_manager.h
diff --git a/chrome/browser/ui/webui/chrome_url_data_manager.h b/chrome/browser/ui/webui/chrome_url_data_manager.h
index c81b6628efb32f599cbf8d81c67806dd4d3f65bb..cdaa54e8c654768f762f8c71177d96f2208dce8d 100644
--- a/chrome/browser/ui/webui/chrome_url_data_manager.h
+++ b/chrome/browser/ui/webui/chrome_url_data_manager.h
@@ -11,8 +11,8 @@
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
+#include "base/message_loop_helpers.h"
 #include "base/synchronization/lock.h"
-#include "base/task.h"
 
 class ChromeURLDataManagerBackend;
 class MessageLoop;
@@ -114,7 +114,7 @@ class ChromeURLDataManager {
    private:
     friend class ChromeURLDataManagerBackend;
     friend class ChromeURLDataManager;
-    friend class DeleteTask<DataSource>;
+    friend class base::DeleteHelper<DataSource>;
 
     // SendResponse invokes this on the IO thread. Notifies the backend to
     // handle the actual work of sending the data.