Remove std:: prefixes from C functions in talk/.

std::memcpy -> memcpy for instance. This change was motivated by a
compile report complaining that std::rand() was used instead of rand(),
probably with a stdlib.h include instead of cstdlib. Use of C functions
without the std:: prefix is a lot more common, so removing std:: to
address this.

BUG=
R=tommi@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/9559004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5657 4adac7df-926f-26a2-2b94-8c16560cd09d

talk/base/messagequeue.h

@@ -28,8 +28,9 @@
 #ifndef TALK_BASE_MESSAGEQUEUE_H_
 #define TALK_BASE_MESSAGEQUEUE_H_
 
+#include <string.h>
+
 #include <algorithm>
-#include <cstring>
 #include <list>
 #include <queue>
 #include <vector>