handle null dep.idRangeStarts

lib/dependencies/HarmonyImportSpecifierDependency.js

@@ -324,7 +324,10 @@ HarmonyImportSpecifierDependency.Template = class HarmonyImportSpecifierDependen
 			// Meaning, the two arrays may not always have the same number of elements, but the last element of
 			// dep.idRangeStarts corresponds to [the starting range position of] the last element of dep.getIds.
 			// Use this to find the correct range end position based on the number of ids that were trimmed.
-			const idx = dep.idRangeStarts.length + (trimmedIds.length - ids.length);
+			const idx =
+				dep.idRangeStarts === undefined
+					? -1 /* trigger failure case below */
+					: dep.idRangeStarts.length + (trimmedIds.length - ids.length);
 			if (idx < 0 || idx >= dep.idRangeStarts.length) {
 				// cspell:ignore minifiers
 				// Should not happen but we can't throw an error here because of backward compatibility with