Created a DownloadManager interface, for use in unit tests..

chrome/browser/download/download_service.cc

 // Copyright (c) 2011 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 "chrome/browser/download/download_service.h"
 
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/download/chrome_download_manager_delegate.h"
 #include "chrome/browser/download/download_service_factory.h"
 #include "chrome/browser/profiles/profile.h"
@@ skipping 33 matching lines @@
     download_manager_created_ = true;
   }
   return manager_.get();
 }
 
 bool DownloadService::HasCreatedDownloadManager() {
   return download_manager_created_;
 }
 
 int DownloadService::DownloadCount() const {
-  return download_manager_created_ ? manager_->in_progress_count() : 0;
+  return download_manager_created_ ? manager_->InProgressCount() : 0;
 }
 
 // static
 int DownloadService::DownloadCountAllProfiles() {
   std::vector<Profile*> profiles(
       g_browser_process->profile_manager()->GetLoadedProfiles());
 
   int count = 0;
   for (std::vector<Profile*>::iterator it = profiles.begin();
        it < profiles.end(); ++it) {
@@ skipping 26 matching lines @@
     // Resetting here will guarantee that any attempts to get the
     // DownloadManager after shutdown will return null.
     //
     // TODO(rdsmith): Figure out how to guarantee when the last reference
     // will be released and make DownloadManager not RefCountedThreadSafe<>.
     manager_.release();
   }
   if (manager_delegate_.get())
     manager_delegate_.release();
 }