Add support for refreshing contents of providers which don't support watchers.

chrome/browser/chromeos/file_system_provider/registry_unittest.cc

 // Copyright 2014 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/chromeos/file_system_provider/registry.h"
 
 #include <string>
 #include <vector>
 
 #include "base/files/file_path.h"
@@ skipping 141 matching lines @@
 }
 
 TEST_F(FileSystemProviderRegistryTest, RememberFileSystem) {
   MountOptions options(kFileSystemId, kDisplayName);
   options.writable = true;
   options.supports_notify_tag = true;
   options.opened_files_limit = kOpenedFilesLimit;
 
   ProvidedFileSystemInfo file_system_info(
       kExtensionId, options, base::FilePath(FILE_PATH_LITERAL("/a/b/c")),
-      false /* configurable */, extensions::SOURCE_FILE);
+      false /* configurable */, true /* watchable */, extensions::SOURCE_FILE);
 
   Watchers watchers;
   watchers[WatcherKey(fake_watcher_.entry_path, fake_watcher_.recursive)] =
       fake_watcher_;
 
   registry_->RememberFileSystem(file_system_info, watchers);
 
   TestingPrefServiceSyncable* const pref_service =
       profile_->GetTestingPrefService();
   ASSERT_TRUE(pref_service);
@@ skipping 95 matching lines @@
                                                              &file_systems));
 }
 
 TEST_F(FileSystemProviderRegistryTest, UpdateWatcherTag) {
   MountOptions options(kFileSystemId, kDisplayName);
   options.writable = true;
   options.supports_notify_tag = true;
 
   ProvidedFileSystemInfo file_system_info(
       kExtensionId, options, base::FilePath(FILE_PATH_LITERAL("/a/b/c")),
-      false /* configurable */, extensions::SOURCE_FILE);
+      false /* configurable */, true /* watchable */, extensions::SOURCE_FILE);
 
   Watchers watchers;
   watchers[WatcherKey(fake_watcher_.entry_path, fake_watcher_.recursive)] =
       fake_watcher_;
 
   registry_->RememberFileSystem(file_system_info, watchers);
 
   fake_watcher_.last_tag = "updated-tag";
   registry_->UpdateWatcherTag(file_system_info, fake_watcher_);
 
@@ skipping 25 matching lines @@
       fake_watcher_.entry_path.value(), &watcher));
 
   std::string last_tag;
   EXPECT_TRUE(watcher->GetStringWithoutPathExpansion(kPrefKeyWatcherLastTag,
                                                      &last_tag));
   EXPECT_EQ(fake_watcher_.last_tag, last_tag);
 }
 
 }  // namespace file_system_provider
 }  // namespace chromeos