Use suffixed {uint,int}{8,16,32,64}_t types.

webrtc/base/systeminfo.h

 /*
  *  Copyright 2008 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.
  */
 
@@ skipping 18 matching lines @@
   SystemInfo();
 
   // The number of CPU Threads in the system.
   static int GetMaxCpus();
   // The number of CPU Threads currently available to this process.
   static int GetCurCpus();
   // Identity of the CPUs.
   Architecture GetCpuArchitecture();
   std::string GetCpuVendor();
   // Total amount of physical memory, in bytes.
-  int64 GetMemorySize();
+  int64_t GetMemorySize();
   // The model name of the machine, e.g. "MacBookAir1,1"
   std::string GetMachineModel();
 
  private:
   static int logical_cpus_;
 };
 
 }  // namespace rtc
 
 #endif  // WEBRTC_BASE_SYSTEMINFO_H__