Implement SysInfo::HardwareModelName() on iOS.

base/sys_info_mac.mm

 // Copyright 2016 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.
 
 #include "base/sys_info.h"
 
 #include <ApplicationServices/ApplicationServices.h>
 #include <CoreServices/CoreServices.h>
 #import <Foundation/Foundation.h>
 #include <mach/mach_host.h>
@@ skipping 83 matching lines @@
 
 // static
 std::string SysInfo::CPUModelName() {
   char name[256];
   size_t len = arraysize(name);
   if (sysctlbyname("machdep.cpu.brand_string", &name, &len, NULL, 0) == 0)
     return name;
   return std::string();
 }
 
+// static
 std::string SysInfo::HardwareModelName() {
   char model[256];
   size_t len = sizeof(model);
   if (sysctlbyname("hw.model", model, &len, NULL, 0) == 0)
     return std::string(model, 0, len);
   return std::string();
 }
 
 }  // namespace base