Roll engine to c88ba37c794f57982374bb53a694301198cad593 (#15053)

* Roll engine to c88ba37c794f57982374bb53a694301198cad593.

Changes since last roll:
  - move generated entry points JSON out of flutter_patched_sdk
  - List missing core lib bigint_patch.dart source for new Bigint implementation (#4735)
  - Skip over .emf-files. (#4739)
  - Roll dart to ee15c8eb689791f6777eb3f6b0a1e9c58ff0671b.

* defaultValue -> orElse

bin/internal/engine.version

-269bab73b6ad8f0e54fcd2b84f278ba857baf4af
+c88ba37c794f57982374bb53a694301198cad593

packages/flutter_tools/lib/src/project.dart

@@ -109,5 +109,5 @@ Future<Match> _firstMatchInFile(File file, RegExp regExp) async {
       .transform(UTF8.decoder)
       .transform(const LineSplitter())
       .map(regExp.firstMatch)
-      .firstWhere((Match match) => match != null, defaultValue: () => null);
+      .firstWhere((Match match) => match != null, orElse: () => null);
 }