Move WriteFile and WriteFileDescriptor from file_util to base namespace.

chrome/renderer/mock_printer.cc

Index: chrome/renderer/mock_printer.cc
diff --git a/chrome/renderer/mock_printer.cc b/chrome/renderer/mock_printer.cc
index 15213e6d7a2de9a6b0a660230c63477a8af088fd..5e43ab014b5570f7c210d8f77228e4873409be05 100644
--- a/chrome/renderer/mock_printer.cc
+++ b/chrome/renderer/mock_printer.cc
@@ -273,8 +273,8 @@ bool MockPrinter::SaveSource(
     return false;
   const uint8* source_data = pages_[page]->source_data();
   uint32 source_size = pages_[page]->source_size();
-  file_util::WriteFile(filepath, reinterpret_cast<const char*>(source_data),
-                       source_size);
+  base::WriteFile(filepath, reinterpret_cast<const char*>(source_data),
+                  source_size);
   return true;
 }