@W-21006714: singleServerCustomTabActivity is malfunctioning (#2831)

Author: JohnsonEricAtSalesforce

libs/SalesforceSDK/src/com/salesforce/androidsdk/ui/LoginActivity.kt

@@ -1526,6 +1526,7 @@ open class LoginActivity : FragmentActivity() {
                 if (activity.viewModel.singleServerCustomTabActivity) {
                     // Show blank page and spinner until PKCE is done.
                     activity.viewModel.loginUrl.value = ABOUT_BLANK
+                    finish()
                 } else {
                     // Don't show server picker if we are re-authenticating with cookie.
                     activity.clearWebView(showServerPicker = !activity.sharedBrowserSession)

libs/SalesforceSDK/src/com/salesforce/androidsdk/ui/LoginViewModel.kt

@@ -515,7 +515,7 @@ open class LoginViewModel(val bootConfig: BootConfig) : ViewModel() {
         private val scope: CoroutineScope = viewModelScope,
     ) : Observer<String?> {
         override fun onChanged(value: String?) {
-            if (!sdkManager.isBrowserLoginEnabled && !viewModel.isUsingFrontDoorBridge && value != null) {
+            if (!sdkManager.isBrowserLoginEnabled && !singleServerCustomTabActivity && !viewModel.isUsingFrontDoorBridge && value != null) {
                 val valueUrl = value.toUri()
                 val loginUrl = viewModel.loginUrl.value?.toUri()
                 val isNewServer = loginUrl?.host != valueUrl.host || loginUrl?.path != valueUrl.path
@@ -563,7 +563,8 @@ open class LoginViewModel(val bootConfig: BootConfig) : ViewModel() {
         private val scope: CoroutineScope = viewModelScope,
     ) : Observer<String> {
         override fun onChanged(value: String) {
-            if (sdkManager.isBrowserLoginEnabled && !viewModel.isUsingFrontDoorBridge) {
+            val useBrowserCustomTab = sdkManager.isBrowserLoginEnabled || singleServerCustomTabActivity
+            if (useBrowserCustomTab && !viewModel.isUsingFrontDoorBridge) {
                 scope.launch {
                     viewModel.browserCustomTabUrl.value = viewModel.getAuthorizationUrl(
                         server = value