Move WriteFile and WriteFileDescriptor from file_util to base namespace.

content/common/gpu/media/video_encode_accelerator_unittest.cc

Index: content/common/gpu/media/video_encode_accelerator_unittest.cc
diff --git a/content/common/gpu/media/video_encode_accelerator_unittest.cc b/content/common/gpu/media/video_encode_accelerator_unittest.cc
index 2fa521786fef6e83c3c91e892e3b4b7146d0ebfb..3977b5082af31e47c0a5a8d67a3edc48b5219b3e 100644
--- a/content/common/gpu/media/video_encode_accelerator_unittest.cc
+++ b/content/common/gpu/media/video_encode_accelerator_unittest.cc
@@ -379,7 +379,7 @@ VEAClient::VEAClient(const TestStream& test_stream,
     base::FilePath out_filename(test_stream_.out_filename);
     // This creates or truncates out_filename.
     // Without it, AppendToFile() will not work.
-    EXPECT_EQ(0, file_util::WriteFile(out_filename, NULL, 0));
+    EXPECT_EQ(0, base::WriteFile(out_filename, NULL, 0));
   }
 
   thread_checker_.DetachFromThread();