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

chrome/browser/app_controller_mac.mm

 // 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.
 
 #import "chrome/browser/app_controller_mac.h"
 
 #include "base/auto_reset.h"
 #include "base/command_line.h"
 #include "base/file_path.h"
 #include "base/mac/foundation_util.h"
@@ skipping 621 matching lines @@
   if (!profile_manager)
     return YES;
 
   std::vector<Profile*> profiles(profile_manager->GetLoadedProfiles());
   for (size_t i = 0; i < profiles.size(); ++i) {
     DownloadService* download_service =
       DownloadServiceFactory::GetForProfile(profiles[i]);
     DownloadManager* download_manager =
         (download_service->HasCreatedDownloadManager() ?
          download_service->GetDownloadManager() : NULL);
-    if (download_manager && download_manager->in_progress_count() > 0) {
-      int downloadCount = download_manager->in_progress_count();
+    if (download_manager && download_manager->InProgressCount() > 0) {
+      int downloadCount = download_manager->InProgressCount();
       if ([self userWillWaitForInProgressDownloads:downloadCount]) {
         // Create a new browser window (if necessary) and navigate to the
         // downloads page if the user chooses to wait.
         Browser* browser = BrowserList::FindBrowserWithProfile(profiles[i]);
         if (!browser) {
           browser = Browser::Create(profiles[i]);
           browser->window()->Show();
         }
         DCHECK(browser);
         browser->ShowDownloadsTab();
@@ skipping 626 matching lines @@
 
 }  // namespace browser
 
 namespace app_controller_mac {
 
 bool IsOpeningNewWindow() {
   return g_is_opening_new_window;
 }
 
 }  // namespace app_controller_mac