Move FileEnumerator to its own file, do some refactoring.

third_party/zlib/google/zip.cc

Index: third_party/zlib/google/zip.cc
diff --git a/third_party/zlib/google/zip.cc b/third_party/zlib/google/zip.cc
index e24449bdb03b8c29af4b7779bbd5122e93b01e76..2e46beded0ed689ef6921de5d1c9d9d64fbbfb05 100644
--- a/third_party/zlib/google/zip.cc
+++ b/third_party/zlib/google/zip.cc
@@ -6,6 +6,7 @@
 
 #include "base/bind.h"
 #include "base/file_util.h"
+#include "base/files/file_enumerator.h"
 #include "base/logging.h"
 #include "base/string16.h"
 #include "base/string_util.h"
@@ -137,9 +138,8 @@ bool ZipWithFilterCallback(const base::FilePath& src_dir,
   }
 
   bool success = true;
-  file_util::FileEnumerator file_enumerator(src_dir, true /* recursive */,
-      file_util::FileEnumerator::FILES |
-      file_util::FileEnumerator::DIRECTORIES);
+  base::FileEnumerator file_enumerator(src_dir, true /* recursive */,
+      base::FileEnumerator::FILES | base::FileEnumerator::DIRECTORIES);
   for (base::FilePath path = file_enumerator.Next(); !path.value().empty();
        path = file_enumerator.Next()) {
     if (!filter_cb.Run(path)) {