Switch C++-style C headers with their C equivalents.

The C++ headers define the C functions within the std:: namespace, but
we mainly don't use the std:: namespace for C functions. Therefore we
should include the C headers.

BUG=1833
R=tommi@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/1917004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@4486 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/test/testsupport/fileutils_unittest.cc b/webrtc/test/testsupport/fileutils_unittest.cc
index 1fd11bf..c38e453 100644
--- a/webrtc/test/testsupport/fileutils_unittest.cc
+++ b/webrtc/test/testsupport/fileutils_unittest.cc
@@ -10,7 +10,8 @@
 
 #include "webrtc/test/testsupport/fileutils.h"
 
-#include <cstdio>
+#include <stdio.h>
+
 #include <list>
 #include <string>
 
@@ -120,9 +121,9 @@
 TEST_F(FileUtilsTest, CreateDirectory) {
   std::string directory = "fileutils-unittest-empty-dir";
   // Make sure it's removed if a previous test has failed:
-  std::remove(directory.c_str());
+  remove(directory.c_str());
   ASSERT_TRUE(webrtc::test::CreateDirectory(directory));
-  std::remove(directory.c_str());
+  remove(directory.c_str());
 }
 
 TEST_F(FileUtilsTest, WorkingDirReturnsValue) {