[rtp_rtcp] lint build/include errors fixed

webrtc/modules/rtp_rtcp/source/ssrc_database.cc

 /*
  *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #include "webrtc/modules/rtp_rtcp/source/ssrc_database.h"
 
 #include <assert.h>
 #include <stdlib.h>
 
+#include <string>
+
 #include "webrtc/system_wrappers/include/critical_section_wrapper.h"
 
 #ifdef _WIN32
+    #include <MMSystem.h> //timeGetTime
     #include <windows.h>
-    #include <MMSystem.h> //timeGetTime
 
 // TODO(hellner): investigate if it is necessary to disable these warnings.
     #pragma warning(disable:4311)
     #pragma warning(disable:4312)
 #else
     #include <stdio.h>
     #include <string.h>
+    #include <sys/time.h>
     #include <time.h>
-    #include <sys/time.h>
 #endif
 
 namespace webrtc {
 SSRCDatabase*
 SSRCDatabase::StaticInstance(CountOperation count_operation)
 {
   SSRCDatabase* impl =
       GetStaticInstance<SSRCDatabase>(count_operation);
   return impl;
 }
@@ skipping 70 matching lines @@
     {
         ssrc = rand();
         ssrc = ssrc <<16;
         ssrc += rand();
 
     } while (ssrc == 0 || ssrc == 0xffffffff);
 
     return ssrc;
 }
 }  // namespace webrtc