Make Android visual test screenshots more deterministic

[BretJohnson]

Make two changes so that Android visual test screenshots are more deterministic,
returning the same thing whether running locally or on CI, part of a single test run
or a batch test run:

1. Use the same nav bar style for the gallery pages and the issues pages. This looks better aesthetically and avoids an issue where issue page screenshots aren't consistent, depending on whether you've ever visited a gallery page or not.

2. Crop the 3 button nav from the bottom of the screen for Android. That UI isn't part of the app
   and the color of the buttons can vary (they temporarily change to a different color when pressed).
   Not including that UI in the screenshots avoids any spurious differences here.

See more details in the Teams chat:
https://teams.microsoft.com/l/message/19:46c9eef68efe400393f538bd778e4718@thread.v2/1691428231798?context=%7B%22contextType%22%3A%22chat%22%7D

[Eilon]

The Teams chat is not accessible to me, but this sounds reasonable.

[Eilon]

Looks like the test is failing on iOS and Windows now: https://dev.azure.com/xamarin/public/_build/results?buildId=92639&view=ms.vss-test-web.build-test-results-tab&runId=2055450&resultId=100012&paneView=debug

Error message
VisualTestUtils.VisualTestFailedException :
Snapshot different than baseline: Issue15330Test.png (12.01% difference)
If the correct baseline has changed (this isn't a a bug), then update the baseline image.
See test attachment or download the build artifacts to get the new snapshot file.


More info: https://aka.ms/visual-test-workflow



Stack trace
   at VisualTestUtils.VisualRegressionTester.Fail(String message)
   at VisualTestUtils.VisualRegressionTester.VerifyMatchesSnapshot(String name, ImageSnapshot actualImage, String environmentName, ITestContext testContext)
   at Microsoft.Maui.AppiumTests.UITestBase.VerifyScreenshot(String name) in /Users/builder/azdo/_work/3/s/src/Controls/tests/UITests/Tests/UITestBase.cs:line 183
   at Microsoft.Maui.AppiumTests.Issues.Issue15330.Issue15330Test() in /Users/builder/azdo/_work/3/s/src/Controls/tests/UITests/Tests/Issues/Issue15330.cs:line 18
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Void** arguments, Signature sig, Boolean isConstructor)
   at System.Reflection.MethodInvoker.Invoke(Object obj, IntPtr* args, BindingFlags invokeAttr)

[Eilon]

Need to fix failing test(s).

[Eilon]

@BretJohnson - iOS and Windows still seem sad 😢

VisualTestUtils.VisualTestFailedException :
Snapshot different than baseline: Issue15330Test.png (6.93% difference)
If the correct baseline has changed (this isn't a a bug), then update the baseline image.
See test attachment or download the build artifacts to get the new snapshot file.


More info: https://aka.ms/visual-test-workflow



Stack trace
   at VisualTestUtils.VisualRegressionTester.Fail(String message)
   at VisualTestUtils.VisualRegressionTester.VerifyMatchesSnapshot(String name, ImageSnapshot actualImage, String environmentName, ITestContext testContext)
   at Microsoft.Maui.AppiumTests.UITestBase.VerifyScreenshot(String name) in /Users/builder/azdo/_work/3/s/src/Controls/tests/UITests/Tests/UITestBase.cs:line 183
   at Microsoft.Maui.AppiumTests.Issues.Issue15330.Issue15330Test() in /Users/builder/azdo/_work/3/s/src/Controls/tests/UITests/Tests/Issues/Issue15330.cs:line 18
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Void** arguments, Signature sig, Boolean isConstructor)
   at System.Reflection.MethodInvoker.Invoke(Object obj, IntPtr* args, BindingFlags invokeAttr)

[Eilon]

Though, the % difference is lower now, so it's getting better 😉