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

webrtc/base/systeminfo.h

Index: webrtc/base/systeminfo.h
diff --git a/webrtc/base/systeminfo.h b/webrtc/base/systeminfo.h
index e2237026fb0a157f5f681d8c159fa8942da6b6da..99d18b296001737948eb6e85d334dd3bd41ca17e 100644
--- a/webrtc/base/systeminfo.h
+++ b/webrtc/base/systeminfo.h
@@ -36,7 +36,7 @@ class SystemInfo {
   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();