Move WriteFile and WriteFileDescriptor from file_util to base namespace.

chrome/browser/diagnostics/diagnostics_controller_unittest.cc

Index: chrome/browser/diagnostics/diagnostics_controller_unittest.cc
diff --git a/chrome/browser/diagnostics/diagnostics_controller_unittest.cc b/chrome/browser/diagnostics/diagnostics_controller_unittest.cc
index 0a408bbe463568a43674f53e51490b316b77a0dc..369dde6ac69dcd1cdfbfa4269408145e69591b5f 100644
--- a/chrome/browser/diagnostics/diagnostics_controller_unittest.cc
+++ b/chrome/browser/diagnostics/diagnostics_controller_unittest.cc
@@ -75,7 +75,7 @@ class DiagnosticsControllerTest : public testing::Test {
     // Just write some random characters into the file tInvaludUsero "corrupt"
     // it.
     const char bogus_data[] = "wwZ2uNYNuyUVzFbDm3DL";
-    file_util::WriteFile(path, bogus_data, arraysize(bogus_data));
+    base::WriteFile(path, bogus_data, arraysize(bogus_data));
   }
 
   scoped_ptr<DiagnosticsModel> model_;