Fix client id is not populated to authflow session in saml flow

ref DEV-2350

Author: louischan-oursky

.vettedpositions

@@ -41,10 +41,10 @@
 /pkg/auth/handler/webapp/auth_entry_point_middleware.go:31:31: requestcontext
 /pkg/auth/handler/webapp/auth_entry_point_middleware.go:32:35: requestcontext
 /pkg/auth/handler/webapp/authflow_change_password.go:96:26: requestcontext
-/pkg/auth/handler/webapp/authflow_controller.go:1000:19: requestcontext
-/pkg/auth/handler/webapp/authflow_controller.go:978:30: requestcontext
-/pkg/auth/handler/webapp/authflow_controller.go:983:24: requestcontext
-/pkg/auth/handler/webapp/authflow_controller.go:991:19: requestcontext
+/pkg/auth/handler/webapp/authflow_controller.go:1001:19: requestcontext
+/pkg/auth/handler/webapp/authflow_controller.go:979:30: requestcontext
+/pkg/auth/handler/webapp/authflow_controller.go:984:24: requestcontext
+/pkg/auth/handler/webapp/authflow_controller.go:992:19: requestcontext
 /pkg/auth/handler/webapp/authflow_create_password.go:132:26: requestcontext
 /pkg/auth/handler/webapp/authflow_enter_oob_otp.go:156:26: requestcontext
 /pkg/auth/handler/webapp/authflow_enter_password.go:138:26: requestcontext

pkg/auth/handler/webapp/authflow_controller.go

@@ -905,6 +905,7 @@ func (c *AuthflowController) makeSessionOptionsFromSAML(ctx context.Context, sam
 	sessionOptions := &authflow.SessionOptions{
 		SAMLSessionID: samlSessionID,
 
+		ClientID:    uiInfo.SAMLServiceProviderID,
 		RedirectURI: uiInfo.RedirectURI,
 		Prompt:      uiInfo.Prompt,
 		LoginHint:   uiInfo.LoginHint,

pkg/lib/saml/samlsession/ui.go

@@ -16,7 +16,7 @@ const (
 )
 
 type SAMLUIInfo struct {
-	// SAMLServiceProviderID is id of the service provider
+	// SAMLServiceProviderID is id of the service provider, and also the corresponding client_id
 	SAMLServiceProviderID string
 	// RedirectURI is the redirect_uri the UI should redirect to.
 	// The redirect_uri in the URL has lower precedence.