Move FileEnumerator to its own file, do some refactoring.

components/autofill/browser/data_driven_test.cc

Index: components/autofill/browser/data_driven_test.cc
diff --git a/components/autofill/browser/data_driven_test.cc b/components/autofill/browser/data_driven_test.cc
index 7717cf7cd751b3ee44380f3d311633072463f5a6..9d0399eaee79ccd31b03c4a521eb3d602d62c216 100644
--- a/components/autofill/browser/data_driven_test.cc
+++ b/components/autofill/browser/data_driven_test.cc
@@ -5,6 +5,7 @@
 #include "components/autofill/browser/data_driven_test.h"
 
 #include "base/file_util.h"
+#include "base/files/file_enumerator.h"
 #include "base/path_service.h"
 #include "base/string_util.h"
 #include "chrome/common/chrome_paths.h"
@@ -36,10 +37,10 @@ void DataDrivenTest::RunDataDrivenTest(
     const base::FilePath& input_directory,
     const base::FilePath& output_directory,
     const base::FilePath::StringType& file_name_pattern) {
-  file_util::FileEnumerator input_files(input_directory,
-                                        false,
-                                        file_util::FileEnumerator::FILES,
-                                        file_name_pattern);
+  base::FileEnumerator input_files(input_directory,
+                                   false,
+                                   base::FileEnumerator::FILES,
+                                   file_name_pattern);
 
   for (base::FilePath input_file = input_files.Next();
        !input_file.empty();