fix setExposureAndFocusPoint

[leftcoding]

Summary

Fix #65. This PR fixes set exposure crashes when switching between cameras by adding a condition when the set is called.

Step to reproduce

• Double click to switch between cameras
• When switching, tap the screen again, to call the exposure point set.

Environments

• System version: Android 10
• Package: ^2.6.2
• Flutter SDK: 2.5.3
• Dart SDK: 2.14.0

Logs

E/AndroidRuntime( 5978): java.lang.AssertionError: The cameraBoundaries should be set (using `ExposurePointFeature.setCameraBoundaries(Size)`) before updating the exposure point.
E/AndroidRuntime( 5978): 	at io.flutter.plugins.camera.features.exposurepoint.ExposurePointFeature.buildExposureRectangle(ExposurePointFeature.java:83)
E/AndroidRuntime( 5978): 	at io.flutter.plugins.camera.features.exposurepoint.ExposurePointFeature.setValue(ExposurePointFeature.java:61)
E/AndroidRuntime( 5978): 	at io.flutter.plugins.camera.Camera.setExposurePoint(Camera.java:803)
E/AndroidRuntime( 5978): 	at io.flutter.plugins.camera.MethodCallHandlerImpl.onMethodCall(MethodCallHandlerImpl.java:183)
E/AndroidRuntime( 5978): 	at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:233)
E/AndroidRuntime( 5978): 	at io.flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:84)
E/AndroidRuntime( 5978): 	at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:865)
E/AndroidRuntime( 5978): 	at android.os.MessageQueue.nativePollOnce(Native Method)
E/AndroidRuntime( 5978): 	at android.os.MessageQueue.next(MessageQueue.java:326)
E/AndroidRuntime( 5978): 	at android.os.Looper.loop(Looper.java:160)
E/AndroidRuntime( 5978): 	at android.app.ActivityThread.main(ActivityThread.java:6713)
E/AndroidRuntime( 5978): 	at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime( 5978): 	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
E/AndroidRuntime( 5978): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:911)

[AlexV525]

Suggested change

	if (_controller?.value.isInitialized != true) {
	return;
	}
	setExposureAndFocusPoint(d, constraints);
	// Only call exposure point updates when the controller is initialized.
	if (_controller?.value.isInitialized == true) {
	setExposureAndFocusPoint(d, constraints);
	}

[AlexV525]

LGTM. Thanks for the fix.

[AlexV525]

@all-contributors Add @leftcoding for bugs.

[allcontributors]

@AlexV525

I've put up a pull request to add @leftcoding! 🎉