Implement SysInfo::CPUArchitecture() on Windows.

base/sys_info.h

Index: base/sys_info.h
===================================================================
--- base/sys_info.h	(revision 158637)
+++ base/sys_info.h	(working copy)
@@ -5,15 +5,14 @@
 #ifndef BASE_SYS_INFO_H_
 #define BASE_SYS_INFO_H_
 
+#include <string>
+
 #include "base/base_export.h"
 #include "base/basictypes.h"
 #include "base/file_path.h"
 #include "base/time.h"
+#include "build/build_config.h"
 
-#include <string>
-
-class FilePath;
-
 namespace base {
 
 class BASE_EXPORT SysInfo {
@@ -51,10 +50,15 @@
                                             int32* minor_version,
                                             int32* bugfix_version);
 
-  // Returns the CPU architecture of the system. Exact return value may differ
-  // across platforms.
+  // Returns the architecture of the running operating system.
+  // Exact return value may differ across platforms.
+  // e.g. a 32-bit x86 kernel on a 64-bit capable CPU will return "x86",
+  //      whereas a x86-64 kernel on the same CPU will return "x86_64"
+  // TODO(thestig) Rename this to OperatingSystemArchitecture().
   static std::string CPUArchitecture();
 
+  // Avoid using this. Use base/cpu.h to get information about the CPU instead.
+  // http://crbug.com/148884
   // Returns the CPU model name of the system. If it can not be figured out,
   // an empty string is returned.
   static std::string CPUModelName();
@@ -66,7 +70,7 @@
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
   // Returns the maximum SysV shared memory segment size.
   static size_t MaxSharedMemorySize();
-#endif // defined(OS_POSIX) && !defined(OS_MACOSX)
+#endif  // defined(OS_POSIX) && !defined(OS_MACOSX)
 
 #if defined(OS_CHROMEOS)
   // Returns the name of the version entry we wish to look up in the
@@ -82,7 +86,7 @@
 
   // Returns the path to the lsb-release file.
   static FilePath GetLsbReleaseFilePath();
-#endif // defined(OS_CHROMEOS)
+#endif  // defined(OS_CHROMEOS)
 
 #if defined(OS_ANDROID)
   // Returns the Android build's codename.
@@ -95,7 +99,7 @@
   static std::string GetDeviceName();
 
   static int DalvikHeapSizeMB();
-#endif // defined(OS_ANDROID)
+#endif  // defined(OS_ANDROID)
 };
 
 }  // namespace base