Enrich fileBrowserPrivate.onFileTransfersUpdated event to support displaying total number of jobs.

ui/file_manager/file_manager/common/js/progress_center_common.js

Index: ui/file_manager/file_manager/common/js/progress_center_common.js
diff --git a/ui/file_manager/file_manager/common/js/progress_center_common.js b/ui/file_manager/file_manager/common/js/progress_center_common.js
index 32311bf9c28c2f8a888fb875a4cde0623310003f..cf12fe14e55f6e6ff5586c7693082ff6217b2327 100644
--- a/ui/file_manager/file_manager/common/js/progress_center_common.js
+++ b/ui/file_manager/file_manager/common/js/progress_center_common.js
@@ -109,6 +109,12 @@ var ProgressCenterItem = function() {
    */
   this.quiet = false;
 
+   /**
+   * If the property is true, this item is syncing.
+   * @type {boolean}
+   */
+  this.sync = false;

[hirono, 2014/08/29 05:38:31]

Although the progress center item is used widely, the variable is only used in
drive_sync_handler.js.
Why does not the DriveSyncHandler have the property?

[iseki, 2014/08/29 08:25:10]

Done.

+
   /**
    * Callback function to cancel the item.
    * @type {function()}