Convert base::MemoryMappedFile to use File instead of PlatformFile.

ui/base/resource/data_pack.h

Index: ui/base/resource/data_pack.h
diff --git a/ui/base/resource/data_pack.h b/ui/base/resource/data_pack.h
index 2ea938f9d1b0325f35bd6c1dffa884a37f76186c..a1a92c58cbaaa093989f4e18d08665cf74228a9b 100644
--- a/ui/base/resource/data_pack.h
+++ b/ui/base/resource/data_pack.h
@@ -12,8 +12,8 @@
 #include <map>
 
 #include "base/basictypes.h"
+#include "base/files/file.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/platform_file.h"
 #include "base/strings/string_piece.h"
 #include "ui/base/layout.h"
 #include "ui/base/resource/resource_handle.h"
@@ -36,7 +36,7 @@ class UI_EXPORT DataPack : public ResourceHandle {
   bool LoadFromPath(const base::FilePath& path);
 
   // Loads a pack file from |file|, returning false on error.
-  bool LoadFromFile(base::PlatformFile file);
+  bool LoadFromFile(base::File file);
 
   // Writes a pack file containing |resources| to |path|. If there are any
   // text resources to be written, their encoding must already agree to the