gdata: Periodic refresh should be active for file lists loaded from cache.

chrome/browser/chromeos/gdata/gdata_file_system.cc

 // 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.
 
 #include "chrome/browser/chromeos/gdata/gdata_file_system.h"
 
 #include <set>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 812 matching lines @@
 
   PrefService* pref_service = profile_->GetPrefs();
   hide_hosted_docs_ = pref_service->GetBoolean(prefs::kDisableGDataHostedFiles);
 
   InitializePreferenceObserver();
 }
 
 void GDataFileSystem::CheckForUpdates() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   ContentOrigin initial_origin = directory_service_->origin();
-  if (initial_origin == FROM_SERVER) {
+  if (initial_origin != REFRESHING) {

[satorux1, 2012/07/30 16:18:26]

looks dangerous. "origin" has been a source of nasty issues...

Is it safe to check updates when the origin is INITIALIZING?

What state do you want to add in addition to FROM_SERVER? Maybe it's better to
do

  if (initial_origin == FROM_SERVER ||
      initial_origin == XXXXX) {


BTW, I wasn't clear for me why you need to change this for the other change
http://codereview.chromium.org/10835031/ to work. Could you explain?

     directory_service_->set_origin(REFRESHING);
     ReloadFeedFromServerIfNeeded(
         initial_origin,
         directory_service_->largest_changestamp(),
         directory_service_->root()->GetFilePath(),
         base::Bind(&GDataFileSystem::OnUpdateChecked,
                    ui_weak_ptr_,
                    initial_origin));
   }
 }
@@ skipping 3435 matching lines @@
   }
 
   PlatformFileInfoProto entry_file_info;
   GDataEntry::ConvertPlatformFileInfoToProto(*file_info, &entry_file_info);
   *entry_proto->mutable_file_info() = entry_file_info;
   if (!callback.is_null())
     callback.Run(GDATA_FILE_OK, entry_proto.Pass());
 }
 
 }  // namespace gdata