Create an AutofillBackend interface

components/webdata/common/web_database_service.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/webdata/common/web_database_service.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "components/webdata/common/web_data_request_manager.h"
 #include "components/webdata/common/web_data_results.h"
@@ skipping 73 matching lines @@
            wds_backend_, false));
 }
 
 WebDatabase* WebDatabaseService::GetDatabaseOnDB() const {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
   if (!wds_backend_)
     return NULL;
   return wds_backend_->database();
 }
 
+scoped_refptr<WebDataServiceBackend> WebDatabaseService::GetBackend() const {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
+  if (!wds_backend_)

[Ilya Sherman, 2013/05/08 00:39:06]

Why can wds_backend_ be NULL?

[Cait (Slow), 2013/05/08 19:16:01]

Because the it does not get created until AddTable() has been called at least
once. 

+    return NULL;
+  return wds_backend_;
+}
+
 void WebDatabaseService::ScheduleDBTask(
     const tracked_objects::Location& from_here,
     const WriteTask& task) {
   if (!wds_backend_) {
     NOTREACHED() << "Task scheduled after Shutdown()";
     return;
   }
 
   scoped_ptr<WebDataRequest> request(
       new WebDataRequest(NULL, wds_backend_->request_manager()));
@@ skipping 46 matching lines @@
     FOR_EACH_OBSERVER(WebDatabaseObserver,
                       observer_list_,
                       WebDatabaseLoaded());
   } else {
     // Notify that the database load failed.
     FOR_EACH_OBSERVER(WebDatabaseObserver,
                       observer_list_,
                       WebDatabaseLoadFailed(status));
   }
 }