Make sure to log errors when failing to send emails (#6754)

api4/user.go

@@ -1016,10 +1016,10 @@ func sendVerificationEmail(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	app.SendEmailVerification(user)
+	err = app.SendEmailVerification(user)
 	if err != nil {
 		// Don't want to leak whether the email is valid or not
-		l4g.Error("Unable to create email verification token: " + err.Error())
+		l4g.Error(err.Error())
 		ReturnStatusOK(w)
 		return
 	}

app/user.go

@@ -1287,12 +1287,10 @@ func SendEmailVerification(user *model.User) *model.AppError {
 	}
 
 	if _, err := GetStatus(user.Id); err != nil {
-		go SendVerifyEmail(user.Email, user.Locale, utils.GetSiteURL(), token.Token)
+		return SendVerifyEmail(user.Email, user.Locale, utils.GetSiteURL(), token.Token)
 	} else {
-		go SendEmailChangeVerifyEmail(user.Email, user.Locale, utils.GetSiteURL(), token.Token)
+		return SendEmailChangeVerifyEmail(user.Email, user.Locale, utils.GetSiteURL(), token.Token)
 	}
-
-	return nil
 }
 
 func VerifyEmailFromToken(userSuppliedTokenString string) *model.AppError {