Move WriteFile and WriteFileDescriptor from file_util to base namespace.

chrome/browser/ui/pdf/pdf_browsertest.cc

Index: chrome/browser/ui/pdf/pdf_browsertest.cc
diff --git a/chrome/browser/ui/pdf/pdf_browsertest.cc b/chrome/browser/ui/pdf/pdf_browsertest.cc
index aeb968381bcb203dff8e67560373aa24160737ef..cceea4b0044968f27919f55245b757e1688c1240 100644
--- a/chrome/browser/ui/pdf/pdf_browsertest.cc
+++ b/chrome/browser/ui/pdf/pdf_browsertest.cc
@@ -186,7 +186,7 @@ class PDFBrowserTest : public InProcessBrowserTest,
       std::vector<unsigned char> png_data;
       gfx::PNGCodec::EncodeBGRASkBitmap(bitmap, false, &png_data);
       if (base::CreateTemporaryFile(&snapshot_filename_)) {
-        file_util::WriteFile(snapshot_filename_,
+        base::WriteFile(snapshot_filename_,
             reinterpret_cast<char*>(&png_data[0]), png_data.size());
       }
     }