Is there an existing issue for this?

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Steps to reproduce

platformPluginDelegate maybe nullable.
use by PlatformPlugin(@NonNull Activity activity, @NonNull PlatformChannel platformChannel)

in setFrameworkHandlesBack function, it will cause NullPointerException

need check platformPluginDelegate, like popSystemNavigator function, to avoid NullPointerException

Expected results

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Actual results

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Flutter Doctor output

3.16.3