Remove deprecated NonThreadSafe usage in net\socket.

net/socket/client_socket_pool_manager_impl.h

Index: net/socket/client_socket_pool_manager_impl.h
diff --git a/net/socket/client_socket_pool_manager_impl.h b/net/socket/client_socket_pool_manager_impl.h
index 7aea01f42de82a339c1c411299dc92e59efa9ef8..3fde3468542689c5e5be0edafe4f3eb3e584a0b8 100644
--- a/net/socket/client_socket_pool_manager_impl.h
+++ b/net/socket/client_socket_pool_manager_impl.h
@@ -13,7 +13,7 @@
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
-#include "base/threading/non_thread_safe.h"
+#include "base/threading/thread_checker.h"
 #include "net/cert/cert_database.h"
 #include "net/http/http_network_session.h"
 #include "net/socket/client_socket_pool_manager.h"
@@ -40,8 +40,7 @@ class SSLConfigService;
 class TransportClientSocketPool;
 class TransportSecurityState;
 
-class ClientSocketPoolManagerImpl : public base::NonThreadSafe,
-                                    public ClientSocketPoolManager,
+class ClientSocketPoolManagerImpl : public ClientSocketPoolManager,
                                     public CertDatabase::Observer {
  public:
   ClientSocketPoolManagerImpl(
@@ -120,6 +119,8 @@ class ClientSocketPoolManagerImpl : public base::NonThreadSafe,
   HTTPProxySocketPoolMap http_proxy_socket_pools_;
   SSLSocketPoolMap ssl_socket_pools_for_proxies_;
 
+  THREAD_CHECKER(thread_checker_);
+
   DISALLOW_COPY_AND_ASSIGN(ClientSocketPoolManagerImpl);
 };