Run Android tests on background thread

[mattjohnsonpint]

Hi. We have copied the Maui TestUtils source code into our project, and use it for running device tests on Android emulators, which we do in our GitHub Actions CI. This has been working well, except that at first we were getting a lot of intermittent keyDispatchingTimedOut errors such as the following:

info: Starting default instrumentation class on io.sentry.dotnet.maui.device.testapp (exit code 0 == success)
info: Running instrumentation class {default} took 43.3624407 seconds
warn: Skipping output line due to key-value-pair parse failure: 'INSTRUMENTATION_RESULT: longMsg=Input dispatching timed out (a751cb4 io.sentry.dotnet.maui.device.testapp/io.sentry.dotnet.maui.device.testapp.TestActivity (server) is not responding. Waited 5051ms for FocusEvent(hasFocus=true))'
info: Short message:
      keyDispatchingTimedOut
fail: No value for 'return-code' provided in instrumentation result. This may indicate a crashed test (see log)
info: Wrote current ADB log to /Users/runner/work/sentry-dotnet/sentry-dotnet/./test_output/adb-logcat-io.sentry.dotnet.maui.device.testapp-default.log
info: Attempting to remove apk 'io.sentry.dotnet.maui.device.testapp'..
info: Successfully uninstalled io.sentry.dotnet.maui.device.testapp
XHarness exit code: 82 (RETURN_CODE_NOT_SET)
Error: The process '/bin/sh' failed with exit code 82

(See getsentry/sentry-dotnet#1927)

After some investigation, we realized this was caused because the headless test runner is executing its tests on the main UI thread. We fixed it in our project with getsentry/sentry-dotnet#1929 some time ago - we no longer get keyDispatchingTimedOut errors.

Since it's been working well for us, I thought I should contribute it back here.

[ghost]

Hey there @mattjohnsonpint! Thank you so much for your PR! Someone from the team will get assigned to your PR shortly and we'll get it reviewed.

[mattjohnsonpint]

Also, I presume the same thing is true for iOS tests, but we haven't set that up yet so I didn't want to change that blindly, but it would be here:

maui/src/TestUtils/src/DeviceTests.Runners/HeadlessRunner/iOS/MauiTestViewController.cs

Lines 29 to 31 in a2947df

	var runner = MauiTestApplicationDelegate.Current.Services.GetRequiredService<HeadlessTestRunner>();
	await runner.RunTestsAsync();

[rmarinho]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 2 pipeline(s).

[mattleibow]

Thanks for this. Once day we will have an actual device test package that shows all the work.

[mattjohnsonpint]

Also, I presume the same thing is true for iOS tests ...

Just a follow-up. We added iOS tests a few weeks ago, and they have been working well. We didn't need to make any similar change.