Disable webapps popout for ephemeral Guest profiles.

WebApps popout is disabled for Guest sessions. Same restriction is added
for ephemeral Guest profiles.

This change is behind disabled |EnableEphemeralGuestProfilesOnDesktop|
flag.
Please see go/ephemeral-guest-profiles for more context.

Bug: 1125474
Change-Id: Ic6bde4313a5107f165eb00ac5d8c0e3ff1c9496f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2461383Reviewed-by: Ramin Halavati <rhalavati@chromium.org>
Reviewed-by: calamity <calamity@chromium.org>
Commit-Queue: Ramin Halavati <rhalavati@chromium.org>
Cr-Commit-Position: refs/heads/master@{#816065}

chrome/browser/ui/web_applications/web_app_dialog_utils.cc

@@ -95,7 +95,7 @@ bool CanCreateWebApp(const Browser* browser) {
 
 bool CanPopOutWebApp(Profile* profile) {
   return AreWebAppsEnabled(profile) && !profile->IsGuestSession() &&
-         !profile->IsOffTheRecord();
+         !profile->IsEphemeralGuestProfile() && !profile->IsOffTheRecord();
 }
 
 void CreateWebAppFromCurrentWebContents(Browser* browser,