SmartLock - Email Hint Request

SignInActivity.kt

private fun initHintRequest() {
    hintRequest = HintRequest.Builder()
            .setHintPickerConfig(
                    CredentialPickerConfig.Builder()
                            .setShowCancelButton(true)
                            .setPrompt(CredentialPickerConfig.Prompt.SIGN_IN)
                            .build()
            )
            .setEmailAddressIdentifierSupported(true)
            .build()
}