Remove use of stl_util's STLDeleteContainerPairSecondPointers from content/.

content/browser/renderer_host/p2p/socket_dispatcher_host.h

Index: content/browser/renderer_host/p2p/socket_dispatcher_host.h
diff --git a/content/browser/renderer_host/p2p/socket_dispatcher_host.h b/content/browser/renderer_host/p2p/socket_dispatcher_host.h
index 04ad89fed75975a54092beddd193d62d0e441c67..436203ce337a1db4912ae1c191ca28e850910f80 100644
--- a/content/browser/renderer_host/p2p/socket_dispatcher_host.h
+++ b/content/browser/renderer_host/p2p/socket_dispatcher_host.h
@@ -8,6 +8,7 @@
 #include <stdint.h>
 
 #include <map>
+#include <memory>
 #include <set>
 #include <string>
 #include <vector>
@@ -66,7 +67,7 @@ class P2PSocketDispatcherHost
   friend struct BrowserThread::DeleteOnThread<BrowserThread::IO>;
   friend class base::DeleteHelper<P2PSocketDispatcherHost>;
 
-  typedef std::map<int, P2PSocketHost*> SocketsMap;
+  typedef std::map<int, std::unique_ptr<P2PSocketHost>> SocketsMap;
 
   class DnsRequest;