Warn when extensions suggest conflicting download filenames

chrome/browser/extensions/api/downloads/downloads_api.h

 // Copyright (c) 2012 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_API_DOWNLOADS_DOWNLOADS_API_H_
 #define CHROME_BROWSER_EXTENSIONS_API_DOWNLOADS_DOWNLOADS_API_H_
 
 #include <set>
 #include <string>
 
 #include "base/files/file_path.h"
 #include "base/memory/singleton.h"
 #include "base/strings/string16.h"
 #include "base/values.h"
 #include "chrome/browser/download/all_download_item_notifier.h"
 #include "chrome/browser/download/download_danger_prompt.h"
 #include "chrome/browser/download/download_path_reservation_tracker.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_function.h"
+#include "chrome/browser/extensions/extension_warning_set.h"
 #include "chrome/common/extensions/api/downloads.h"
 #include "content/public/browser/download_item.h"
 #include "content/public/browser/download_manager.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
 class DownloadFileIconExtractor;
 class DownloadQuery;
 
 namespace content {
@@ skipping 261 matching lines @@
 // onCreated and onErased events.
 class ExtensionDownloadsEventRouter : public extensions::EventRouter::Observer,
                                       public content::NotificationObserver,
                                       public AllDownloadItemNotifier::Observer {
  public:
   typedef base::Callback<void(
       const base::FilePath& changed_filename,
       DownloadPathReservationTracker::FilenameConflictAction)>
     FilenameChangedCallback;
 
+  // The logic for how to handle conflicting filename suggestions from multiple
+  // extensions is split out here for testing.
+  static void DetermineFilenameInternal(
+      const base::FilePath& filename,
+      extensions::api::downloads::FilenameConflictAction conflict_action,
+      const std::string& suggesting_extension_id,
+      const base::Time& suggesting_install_time,
+      const std::string& incumbent_extension_id,
+      const base::Time& incumbent_install_time,
+      std::string* winner_extension_id,
+      base::FilePath* determined_filename,
+      extensions::api::downloads::FilenameConflictAction*
+        determined_conflict_action,
+      extensions::ExtensionWarningSet* warnings);
+
   // A downloads.onDeterminingFilename listener has returned. If the extension
   // wishes to override the download's filename, then |filename| will be
   // non-empty. |filename| will be interpreted as a relative path, appended to
   // the default downloads directory. If the extension wishes to overwrite any
   // existing files, then |overwrite| will be true. Returns true on success,
   // false otherwise.
   static bool DetermineFilename(
       Profile* profile,
       bool include_incognito,
       const std::string& ext_id,
@@ skipping 57 matching lines @@
 
   Profile* profile_;
   AllDownloadItemNotifier notifier_;
   std::set<const extensions::Extension*> shelf_disabling_extensions_;
   content::NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionDownloadsEventRouter);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_DOWNLOADS_DOWNLOADS_API_H_