net: Update FileStream to use base::File instead of PlatformFile.

net/url_request/url_request_file_job.cc

Index: net/url_request/url_request_file_job.cc
diff --git a/net/url_request/url_request_file_job.cc b/net/url_request/url_request_file_job.cc
index f0963b668f45d9cc554a0d3106bf19bf8f864b57..7db8d818836bf77fb9398a1f3cbd4327f5030e4a 100644
--- a/net/url_request/url_request_file_job.cc
+++ b/net/url_request/url_request_file_job.cc
@@ -229,9 +229,9 @@ void URLRequestFileJob::DidFetchMetaInfo(const FileMetaInfo* meta_info) {
     return;
   }
 
-  int flags = base::PLATFORM_FILE_OPEN |
-              base::PLATFORM_FILE_READ |
-              base::PLATFORM_FILE_ASYNC;
+  int flags = base::File::FLAG_OPEN |
+              base::File::FLAG_READ |
+              base::File::FLAG_ASYNC;
   int rv = stream_->Open(file_path_, flags,
                          base::Bind(&URLRequestFileJob::DidOpen,
                                     weak_ptr_factory_.GetWeakPtr()));