[camera] Remove usage of _ambiguate method in example (#6555)

Author: nilsreichardt

packages/camera/camera/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 0.10.0+4
+
+* Removes usage of `_ambiguate` method in example.
+* Updates minimum Flutter version to 3.0.
+
 ## 0.10.0+3
 
 * Updates code for `no_leading_underscores_for_local_identifiers` lint.

packages/camera/camera/example/lib/main.dart

@@ -72,7 +72,7 @@ class _CameraExampleHomeState extends State<CameraExampleHome>
   @override
   void initState() {
     super.initState();
-    _ambiguate(WidgetsBinding.instance)?.addObserver(this);
+    WidgetsBinding.instance.addObserver(this);
 
     _flashModeControlRowAnimationController = AnimationController(
       duration: const Duration(milliseconds: 300),
@@ -102,7 +102,7 @@ class _CameraExampleHomeState extends State<CameraExampleHome>
 
   @override
   void dispose() {
-    _ambiguate(WidgetsBinding.instance)?.removeObserver(this);
+    WidgetsBinding.instance.removeObserver(this);
     _flashModeControlRowAnimationController.dispose();
     _exposureModeControlRowAnimationController.dispose();
     super.dispose();
@@ -585,7 +585,7 @@ class _CameraExampleHomeState extends State<CameraExampleHome>
     }
 
     if (_cameras.isEmpty) {
-      _ambiguate(SchedulerBinding.instance)?.addPostFrameCallback((_) async {
+      SchedulerBinding.instance.addPostFrameCallback((_) async {
         showInSnackBar('No camera found.');
       });
       return const Text('None');
@@ -1079,10 +1079,3 @@ Future<void> main() async {
   }
   runApp(const CameraApp());
 }
-
-/// This allows a value of type T or T? to be treated as a value of type T?.
-///
-/// We use this so that APIs that have become non-nullable can still be used
-/// with `!` and `?` on the stable branch.
-// TODO(ianh): Remove this once we roll stable in late 2021.
-T? _ambiguate<T>(T? value) => value;

packages/camera/camera/example/pubspec.yaml

@@ -4,7 +4,7 @@ publish_to: none
 
 environment:
   sdk: ">=2.14.0 <3.0.0"
-  flutter: ">=2.10.0"
+  flutter: ">=3.0.0"
 
 dependencies:
   camera:

packages/camera/camera/pubspec.yaml

@@ -4,11 +4,11 @@ description: A Flutter plugin for controlling the camera. Supports previewing
   Dart.
 repository: https://github.com/flutter/plugins/tree/main/packages/camera/camera
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+camera%22
-version: 0.10.0+3
+version: 0.10.0+4
 
 environment:
   sdk: ">=2.14.0 <3.0.0"
-  flutter: ">=2.10.0"
+  flutter: ">=3.0.0"
 
 flutter:
   plugin: