Migrate to null aware elements - Part 2 (flutter#172306)

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Replace null checks with null aware elements - part 2

Part of flutter#172188

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- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
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Author: jamilsaadeh97

packages/flutter_goldens/lib/flutter_goldens.dart

@@ -234,7 +234,7 @@ abstract class FlutterGoldenFileComparator extends GoldenFileComparator {
     );
     return Uri.parse(
       <String>[
-        if (namePrefix != null) namePrefix!,
+        ?namePrefix,
         basedir.pathSegments[basedir.pathSegments.length - 2],
         golden.toString(),
       ].join('.'),

packages/flutter_localizations/lib/src/cupertino_localizations.dart

@@ -357,12 +357,12 @@ abstract class GlobalCupertinoLocalizations implements CupertinoLocalizations {
 
   @override
   List<String> get timerPickerHourLabels => <String>[
-    if (timerPickerHourLabelZero != null) timerPickerHourLabelZero!,
-    if (timerPickerHourLabelOne != null) timerPickerHourLabelOne!,
-    if (timerPickerHourLabelTwo != null) timerPickerHourLabelTwo!,
-    if (timerPickerHourLabelFew != null) timerPickerHourLabelFew!,
-    if (timerPickerHourLabelMany != null) timerPickerHourLabelMany!,
-    if (timerPickerHourLabelOther != null) timerPickerHourLabelOther!,
+    ?timerPickerHourLabelZero,
+    ?timerPickerHourLabelOne,
+    ?timerPickerHourLabelTwo,
+    ?timerPickerHourLabelFew,
+    ?timerPickerHourLabelMany,
+    ?timerPickerHourLabelOther,
   ];
 
   /// Subclasses should provide the optional zero pluralization of [timerPickerMinuteLabel] based on the ARB file.
@@ -405,12 +405,12 @@ abstract class GlobalCupertinoLocalizations implements CupertinoLocalizations {
 
   @override
   List<String> get timerPickerMinuteLabels => <String>[
-    if (timerPickerMinuteLabelZero != null) timerPickerMinuteLabelZero!,
-    if (timerPickerMinuteLabelOne != null) timerPickerMinuteLabelOne!,
-    if (timerPickerMinuteLabelTwo != null) timerPickerMinuteLabelTwo!,
-    if (timerPickerMinuteLabelFew != null) timerPickerMinuteLabelFew!,
-    if (timerPickerMinuteLabelMany != null) timerPickerMinuteLabelMany!,
-    if (timerPickerMinuteLabelOther != null) timerPickerMinuteLabelOther!,
+    ?timerPickerMinuteLabelZero,
+    ?timerPickerMinuteLabelOne,
+    ?timerPickerMinuteLabelTwo,
+    ?timerPickerMinuteLabelFew,
+    ?timerPickerMinuteLabelMany,
+    ?timerPickerMinuteLabelOther,
   ];
 
   /// Subclasses should provide the optional zero pluralization of [timerPickerSecondLabel] based on the ARB file.
@@ -453,12 +453,12 @@ abstract class GlobalCupertinoLocalizations implements CupertinoLocalizations {
 
   @override
   List<String> get timerPickerSecondLabels => <String>[
-    if (timerPickerSecondLabelZero != null) timerPickerSecondLabelZero!,
-    if (timerPickerSecondLabelOne != null) timerPickerSecondLabelOne!,
-    if (timerPickerSecondLabelTwo != null) timerPickerSecondLabelTwo!,
-    if (timerPickerSecondLabelFew != null) timerPickerSecondLabelFew!,
-    if (timerPickerSecondLabelMany != null) timerPickerSecondLabelMany!,
-    if (timerPickerSecondLabelOther != null) timerPickerSecondLabelOther!,
+    ?timerPickerSecondLabelZero,
+    ?timerPickerSecondLabelOne,
+    ?timerPickerSecondLabelTwo,
+    ?timerPickerSecondLabelFew,
+    ?timerPickerSecondLabelMany,
+    ?timerPickerSecondLabelOther,
   ];
 
   /// A [LocalizationsDelegate] for [CupertinoLocalizations].

packages/integration_test/test/binding_fail_test.dart

@@ -91,7 +91,7 @@ Future<Map<String, dynamic>?> _runTest(String scriptPath) async {
                 if (json is List<dynamic>) {
                   return json.cast();
                 }
-                return <Map<String, dynamic>>[if (json != null) json as Map<String, dynamic>];
+                return <Map<String, dynamic>>[?json as Map<String, dynamic>?];
               })
               .where((Map<String, dynamic> testEvent) => testEvent['type'] == 'print')
               .map((Map<String, dynamic> printEvent) => printEvent['message'] as String)