Move FileEnumerator to its own file, do some refactoring.

chrome/browser/importer/firefox3_importer.cc

Index: chrome/browser/importer/firefox3_importer.cc
diff --git a/chrome/browser/importer/firefox3_importer.cc b/chrome/browser/importer/firefox3_importer.cc
index 516031071c3b94cea3e1b2d06f3f088220d6e6bc..b673f574a8c870fa9f78ac7d4b6207493653c5f3 100644
--- a/chrome/browser/importer/firefox3_importer.cc
+++ b/chrome/browser/importer/firefox3_importer.cc
@@ -7,6 +7,7 @@
 #include <set>
 
 #include "base/file_util.h"
+#include "base/files/file_enumerator.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "base/stl_util.h"
@@ -453,8 +454,7 @@ void Firefox3Importer::GetSearchEnginesXMLFiles(
 #endif
 
   // Get search engine definition from file system.
-  file_util::FileEnumerator engines(app_path, false,
-                                    file_util::FileEnumerator::FILES);
+  base::FileEnumerator engines(app_path, false, base::FileEnumerator::FILES);
   for (base::FilePath engine_path = engines.Next();
        !engine_path.value().empty(); engine_path = engines.Next()) {
     files->push_back(engine_path);