Update ProfilePickerHandler to cover ephemeral Guest profiles.

Updates ProfilePickerHandler to record ephemeral Guest profiles launch
similar to off the record Guest profiles.

Please see go/ephemeral-guest-profiles for more context.

Bug: 1125474
Change-Id: I12625f7db4addfe6f8dcd7bc05584dbf45d404c8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2574755Reviewed-by: David Roger <droger@chromium.org>
Commit-Queue: Ramin Halavati <rhalavati@chromium.org>
Cr-Commit-Position: refs/heads/master@{#834656}

chrome/browser/ui/webui/signin/profile_picker_handler.cc

@@ -527,7 +527,7 @@ void ProfilePickerHandler::OnSwitchToProfileComplete(
 
   if (new_profile) {
     RecordProfilePickerAction(ProfilePickerAction::kLaunchNewProfile);
-  } else if (profile->IsGuestSession()) {
+  } else if (profile->IsGuestSession() || profile->IsEphemeralGuestProfile()) {
     RecordProfilePickerAction(ProfilePickerAction::kLaunchGuestProfile);
   } else {
     RecordProfilePickerAction(