Fix unrecognized selector for isiOSAppOnMac on early iOS 14 betas (#6987)

Author: paulb777

GoogleUtilities.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name             = 'GoogleUtilities'
-  s.version          = '7.1.0'
+  s.version          = '7.1.1'
   s.summary          = 'Google Utilities for iOS (plus community support for macOS and tvOS)'
 
   s.description      = <<-DESC

GoogleUtilities/CHANGELOG.md

@@ -1,4 +1,7 @@
-# 7.1.0 -- Unreleased
+# 7.1.1
+- Fix `unrecognized selector` for isiOSAppOnMac on early iOS 14 betas. (#6969)
+
+# 7.1.0
 - Added `NSURLSession` promise extension. (#6753)
 - `ios_on_mac` option added to `GULAppEnvironmentUtil.applePlatform()`. (#6799)
 - Fixed completion handler issue in `GULAppDelegateSwizzler` for

GoogleUtilities/Environment/third_party/GULAppEnvironmentUtil.m

@@ -272,10 +272,11 @@ + (NSString *)applePlatform {
 #if TARGET_OS_MACCATALYST
   applePlatform = @"maccatalyst";
 #elif TARGET_OS_IOS
-
 #if defined(__IPHONE_14_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= 140000
   if (@available(iOS 14.0, *)) {
-    applePlatform = [NSProcessInfo processInfo].isiOSAppOnMac ? @"ios_on_mac" : @"ios";
+    // Early iOS 14 betas do not include isiOSAppOnMac (#6969)
+    applePlatform = ([[NSProcessInfo processInfo] respondsToSelector:@selector(isiOSAppOnMac)] &&
+                      [NSProcessInfo processInfo].isiOSAppOnMac) ? @"ios_on_mac" : @"ios";
   } else {
     applePlatform = @"ios";
   }