iOS: Cache the result of IsRunningOnIOS10OrLater()

base/ios/ios_util.mm

Index: base/ios/ios_util.mm
diff --git a/base/ios/ios_util.mm b/base/ios/ios_util.mm
index de9adb92ca141a922a78fd2a0da734f9dccbc695..2402d30ab06a89542c67b1c9e03149b4bb54e6ae 100644
--- a/base/ios/ios_util.mm
+++ b/base/ios/ios_util.mm
@@ -29,11 +29,13 @@ namespace base {
 namespace ios {
 
 bool IsRunningOnIOS10OrLater() {
-  return IsRunningOnOrLater(10, 0, 0);
+  static const bool is_running_on_or_later = IsRunningOnOrLater(10, 0, 0);
+  return is_running_on_or_later;
 }
 
 bool IsRunningOnIOS11OrLater() {
-  return IsRunningOnOrLater(11, 0, 0);
+  static const bool is_running_on_or_later = IsRunningOnOrLater(11, 0, 0);
+  return is_running_on_or_later;
 }
 
 bool IsRunningOnOrLater(int32_t major, int32_t minor, int32_t bug_fix) {