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

chrome/browser/chromeos/gdata/gdata_file_system.cc

Index: chrome/browser/chromeos/gdata/gdata_file_system.cc
diff --git a/chrome/browser/chromeos/gdata/gdata_file_system.cc b/chrome/browser/chromeos/gdata/gdata_file_system.cc
index 8a58515fd61042604cdf8369d4999c8195d46556..c4e23ee80049a847ecad35ab205a0bd3ca51b755 100644
--- a/chrome/browser/chromeos/gdata/gdata_file_system.cc
+++ b/chrome/browser/chromeos/gdata/gdata_file_system.cc
@@ -1052,7 +1052,10 @@ void GDataFileSystem::OnGetAccountMetadata(
                    << ", server = "
                    << account_metadata->largest_changestamp();
     }
-    directory_service_->set_origin(initial_origin);
+    // If our cache holds the latest state from the server, change the
+    // state to FROM_SERVER.
+    directory_service_->set_origin(
+        initial_origin == FROM_CACHE ? FROM_SERVER : initial_origin);
     changes_detected = false;
   }