Use a direct include of strings headers in content/browser/, part 2.

content/browser/ssl/ssl_policy_backend.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_SSL_SSL_POLICY_BACKEND_H_
 #define CONTENT_BROWSER_SSL_SSL_POLICY_BACKEND_H_
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
-#include "base/string16.h"
+#include "base/strings/string16.h"
 #include "net/cert/x509_certificate.h"
 
 namespace content {
 class NavigationControllerImpl;
 class SSLHostState;
 
 class SSLPolicyBackend {
  public:
   explicit SSLPolicyBackend(NavigationControllerImpl* controller);
 
@@ skipping 18 matching lines @@
   SSLHostState* ssl_host_state_;
 
   NavigationControllerImpl* controller_;
 
   DISALLOW_COPY_AND_ASSIGN(SSLPolicyBackend);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_SSL_SSL_POLICY_BACKEND_H_