drive: Rename drive::DriveFileSystemTest to drive::FileSystemTest

chrome/browser/chromeos/drive/debug_info_collector.cc

Index: chrome/browser/chromeos/drive/debug_info_collector.cc
diff --git a/chrome/browser/chromeos/drive/debug_info_collector.cc b/chrome/browser/chromeos/drive/debug_info_collector.cc
index 5be498f698adce37d27a50874eb0abd4decf78b5..f13263b31bde480bd5af9ebb7080fec2d8905a37 100644
--- a/chrome/browser/chromeos/drive/debug_info_collector.cc
+++ b/chrome/browser/chromeos/drive/debug_info_collector.cc
@@ -38,9 +38,9 @@ void DebugInfoCollector::GetMetadata(
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!callback.is_null());
 
-  // Currently, this is just a proxy to the DriveFileSystem.
+  // Currently, this is just a proxy to the FileSystem.
   // TODO(hidehiko): Move the implementation to here to simplify the
-  // DriveFileSystem's implementation. crbug.com/237088
+  // FileSystem's implementation. crbug.com/237088
   file_system_->GetMetadata(callback);
 }