After requesting not granted permissions, the result should be dispatched on main thread

[korzonkiee]

Description

Seeing the following crash reported multiple times in Sentry:

java.lang.RuntimeException: Methods marked with @UiThread must be executed on the main thread. Current thread: DefaultDispatcher-worker-1
    at io.flutter.embedding.engine.FlutterJNI.ensureRunningOnMainThread(FlutterJNI.java:37)
    at io.flutter.embedding.engine.FlutterJNI.dispatchPlatformMessage(FlutterJNI.java:1)
    at mb.c.d(DartMessenger.java:79)
    at mb.a$c.c(DartExecutor.java:4)
    at mb.a.c(DartExecutor.java:3)
    at yb.d$c$a.a(EventChannel.java:50)
    at y1.j1.e(CameraPermissions.kt:166)
    at io.flutter.embedding.engine.c$c.i(FlutterEngineConnectionRegistry.java:21)
    at io.flutter.embedding.engine.c.e(FlutterEngineConnectionRegistry.java:14)
    at io.flutter.embedding.android.f.y(FlutterActivityAndFragmentDelegate.java:60)
    at io.flutter.embedding.android.e.onRequestPermissionsResult(FlutterActivity.java:11)
    at android.app.Activity.requestPermissions(Activity.java:5633)
    at androidx.core.app.b$b.b(ActivityCompat.java:1)
    at androidx.core.app.b.r(ActivityCompat.java:140)
    at y1.j1.g(CameraPermissions.kt:100)
    at y1.j1$b.invokeSuspend(CameraPermissions.kt:48)
    at kotlin.coroutines.jvm.internal.a.resumeWith(ContinuationImpl.kt:12)
    at nd.r0.run(DispatchedTask.kt:124)
    at sd.o$a.run(LimitedDispatcher.kt:4)
    at ud.k.run(Tasks.kt:3)
    at ud.a.z(CoroutineScheduler.kt:1)
    at ud.a$c.d(CoroutineScheduler.kt:15)
    at ud.a$c.p(CoroutineScheduler.kt:29)
    at ud.a$c.run(CoroutineScheduler.kt:1)

After some investigation, it turned out that after requesting the not-granted permissions, the callback function is invoked from the IO thread, which then leads to the java.lang.RuntimeException: Methods marked with @UiThread must be executed on the main thread. In order to fix it, we must dispatch the callback invocation to the main thread, similarily as in the case of requesting audio permission.

Closes #450

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• ✅ I ran flutter analyze without any issues.

Breaking Change

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[lively-bigyan]

This solution didn't work for me. It wasn't just the sentry logs that were crashing; the app was actively crashing. I have posted a fix on #511.