[Dynamic Links] Reduce memory stress on WebKit API (#8847)

Author: ncooke3

FirebaseDynamicLinks/CHANGELOG.md

@@ -1,5 +1,6 @@
 # v8.9.0
 - [fixed] Fixed Shortlink regression involving underscores and dashes introduced in 8.8.0. (#8786)
+- [fixed] Reduce memory stress on `WebKit` API. #8847
 
 # v8.8.0
 - [fixed] Firebase dynamic links with custom domain will only work if the custom domain has a trailing '/'. (#7087)

FirebaseDynamicLinks/Sources/FIRDLDefaultRetrievalProcessV2.m

@@ -245,10 +245,7 @@ - (void)fetchLocaleFromWebView {
   if (_jsExecutor) {
     return;
   }
-  NSString *jsString = @"window.generateFingerprint=function(){try{var "
-                       @"languageCode=navigator.languages?navigator.languages[0]:navigator."
-                       @"language;return languageCode;}catch(b){return"
-                        "}};";
+  NSString *jsString = @"window.generateFingerprint=()=>navigator.language||''";
   _jsExecutor = [[FIRDLJavaScriptExecutor alloc] initWithDelegate:self script:jsString];
 }