rename for consistency with update_effect

Author: Rich-Harris

packages/svelte/src/internal/client/runtime.js

@@ -644,7 +644,8 @@ function infinite_loop_guard() {
 }
 
 function flush_queued_root_effects() {
-	let prev_updating = is_updating_effect;
+	let was_updating_effect = is_updating_effect;
+
 	try {
 		var flush_count = 0;
 		is_updating_effect = true;
@@ -672,7 +673,7 @@ function flush_queued_root_effects() {
 		}
 	} finally {
 		is_flushing = false;
-		is_updating_effect = prev_updating;
+		is_updating_effect = was_updating_effect;
 
 		last_scheduled_effect = null;
 		if (DEV) {