MD settings: Storage: Add DELETE button for deleting Drive offline files.

chrome/browser/ui/webui/settings/chromeos/device_storage_handler.cc

 // Copyright 2016 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/ui/webui/settings/chromeos/device_storage_handler.h"
 
 #include <algorithm>
 #include <numeric>
 #include <string>
 
@@ skipping 199 matching lines @@
                          base::FundamentalValue(true));
   updating_drive_cache_size_ = true;
   file_system->CalculateCacheSize(
       base::Bind(&StorageHandler::OnGetDriveCacheSize, base::Unretained(this)));
 }
 
 void StorageHandler::OnGetDriveCacheSize(int64_t size) {
   updating_drive_cache_size_ = false;
   CallJavascriptFunction("cr.webUIListenerCallback",
                          base::StringValue("storage-drive-cache-size-changed"),
-                         base::StringValue(ui::FormatBytes(size)));
+                         base::StringValue(ui::FormatBytes(size)),
+                         base::FundamentalValue(size > 0));
 }
 
 void StorageHandler::UpdateBrowsingDataSize() {
   if (updating_browsing_data_size_)
     return;
   updating_browsing_data_size_ = true;
 
   has_browser_cache_size_ = false;
   has_browser_site_data_size_ = false;
   Profile* const profile = Profile::FromWebUI(web_ui());
@@ skipping 149 matching lines @@
                          base::StringValue("storage-android-size-changed"),
                          base::StringValue(size_string));
 }
 
 void StorageHandler::OnClearDriveCacheDone(bool success) {
   UpdateDriveCacheSize();
 }
 
 }  // namespace settings
 }  // namespace chromeos