Compile ios helpers on mac as well.

webrtc/sdk/objc/Framework/Classes/helpers.mm

 /*
  *  Copyright (c) 2015 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.
  */
 
-#if defined(WEBRTC_IOS)
 
 #import <AVFoundation/AVFoundation.h>
 #import <Foundation/Foundation.h>
 #import <sys/sysctl.h>
+#if defined(WEBRTC_IOS)
 #import <UIKit/UIKit.h>
+#endif
 
 #include <memory>
 
 #include "webrtc/base/checks.h"
 #include "webrtc/base/logging.h"
 #include "webrtc/sdk/objc/Framework/Classes/helpers.h"
 
 namespace webrtc {
 namespace ios {
 
+#if defined(WEBRTC_IOS)
 bool isOperatingSystemAtLeastVersion(double version) {
   return GetSystemVersion() >= version;
 }
+#endif
 
 NSString* NSStringFromStdString(const std::string& stdString) {
   // std::string may contain null termination character so we construct
   // using length.
   return [[NSString alloc] initWithBytes:stdString.data()
                                   length:stdString.length()
                                 encoding:NSUTF8StringEncoding];
 }
 
 std::string StdStringFromNSString(NSString* nsString) {
@@ skipping 14 matching lines @@
   return true;
 }
 
 // TODO(henrika): see if it is possible to move to GetThreadName in
 // platform_thread.h and base it on pthread methods instead.
 std::string GetCurrentThreadDescription() {
   NSString* name = [NSString stringWithFormat:@"%@", [NSThread currentThread]];
   return StdStringFromNSString(name);
 }
 
+#if defined(WEBRTC_IOS)
 std::string GetAudioSessionCategory() {
   NSString* category = [[AVAudioSession sharedInstance] category];
   return StdStringFromNSString(category);
 }
 
 std::string GetSystemName() {
   NSString* osName = [[UIDevice currentDevice] systemName];
   return StdStringFromNSString(osName);
 }
 
 std::string GetSystemVersionAsString() {
   NSString* osVersion = [[UIDevice currentDevice] systemVersion];
   return StdStringFromNSString(osVersion);
 }
 
 double GetSystemVersion() {
   static dispatch_once_t once_token;
   static double system_version;
   dispatch_once(&once_token, ^{
     system_version = [UIDevice currentDevice].systemVersion.doubleValue;
   });
   return system_version;
 }
 
 std::string GetDeviceType() {
   NSString* deviceModel = [[UIDevice currentDevice] model];
   return StdStringFromNSString(deviceModel);
 }
+#endif
 
 std::string GetDeviceName() {
   size_t size;
   sysctlbyname("hw.machine", NULL, &size, NULL, 0);
   std::unique_ptr<char[]> machine;
   machine.reset(new char[size]);
   sysctlbyname("hw.machine", machine.get(), &size, NULL, 0);
   return std::string(machine.get());
 }
 
@@ skipping 25 matching lines @@
   }
   LOG(LS_WARNING) << "webrtc::ios::GetLowPowerModeEnabled() is not "
                      "supported. Requires at least iOS 9.0";
   return false;
 }
 #endif
 
 }  // namespace ios
 }  // namespace webrtc
 
-#endif  // defined(WEBRTC_IOS)