Revert "Speed up first asset load by encoding asset manifest in binary rather than JSON (#113637)" (#116662)

This reverts commit 56cad89.

Author: Casey Hillers

dev/benchmarks/microbenchmarks/lib/foundation/decode_and_parse_asset_manifest.dart

@@ -3,9 +3,9 @@
 // found in the LICENSE file.
 
 import 'dart:convert';
-import 'dart:typed_data';
 
-import 'package:flutter/services.dart' show PlatformAssetBundle, StandardMessageCodec;
+import 'package:flutter/foundation.dart';
+import 'package:flutter/services.dart' show PlatformAssetBundle;
 import 'package:flutter/widgets.dart';
 
 import '../common.dart';
@@ -18,14 +18,16 @@ void main() async {
   final BenchmarkResultPrinter printer = BenchmarkResultPrinter();
   WidgetsFlutterBinding.ensureInitialized();
   final Stopwatch watch = Stopwatch();
+  final PlatformAssetBundle bundle = PlatformAssetBundle();
 
-  final ByteData assetManifest = await loadAssetManifest();
-
+  final ByteData assetManifestBytes = await bundle.load('money_asset_manifest.json');
   watch.start();
   for (int i = 0; i < _kNumIterations; i++) {
-    // This is effectively a test.
+    bundle.clear();
+    final String json = utf8.decode(assetManifestBytes.buffer.asUint8List());
+    // This is a test, so we don't need to worry about this rule.
     // ignore: invalid_use_of_visible_for_testing_member
-    AssetImage.parseAssetManifest(assetManifest);
+    await AssetImage.manifestParser(json);
   }
   watch.stop();
 
@@ -38,49 +40,3 @@ void main() async {
 
   printer.printToStdout();
 }
-
-final RegExp _extractRatioRegExp = RegExp(r'/?(\d+(\.\d*)?)x$');
-
-Future<ByteData> loadAssetManifest() async {
-  double parseScale(String key) {
-    final Uri assetUri = Uri.parse(key);
-    String directoryPath = '';
-    if (assetUri.pathSegments.length > 1) {
-      directoryPath = assetUri.pathSegments[assetUri.pathSegments.length - 2];
-    }
-    final Match? match = _extractRatioRegExp.firstMatch(directoryPath);
-    if (match != null && match.groupCount > 0) {
-      return double.parse(match.group(1)!);
-    }
-    return 1.0;
-  }
-
-  final Map<String, dynamic> result = <String, dynamic>{};
-  final PlatformAssetBundle bundle = PlatformAssetBundle();
-
-  // For the benchmark, we use the older JSON format and then convert it to the modern binary format.
-  final ByteData jsonAssetManifestBytes = await bundle.load('money_asset_manifest.json');
-  final String jsonAssetManifest = utf8.decode(jsonAssetManifestBytes.buffer.asUint8List());
-
-  final Map<String, dynamic> assetManifest = json.decode(jsonAssetManifest) as Map<String, dynamic>;
-
-  for (final MapEntry<String, dynamic> manifestEntry in assetManifest.entries) {
-    final List<dynamic> resultVariants = <dynamic>[];
-    final List<String> entries = (manifestEntry.value as List<dynamic>).cast<String>();
-    for (final String variant in entries) {
-      if (variant == manifestEntry.key) {
-        // With the newer binary format, don't include the main asset in it's
-        // list of variants. This reduces parsing time at runtime.
-        continue;
-      }
-      final Map<String, dynamic> resultVariant = <String, dynamic>{};
-      final double variantDevicePixelRatio = parseScale(variant);
-      resultVariant['asset'] = variant;
-      resultVariant['dpr'] = variantDevicePixelRatio;
-      resultVariants.add(resultVariant);
-    }
-    result[manifestEntry.key] = resultVariants;
-  }
-
-  return const StandardMessageCodec().encodeMessage(result)!;
-}

dev/integration_tests/flutter_gallery/test/example_code_parser_test.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'dart:async';
-
 import 'package:flutter/services.dart';
 import 'package:flutter_gallery/gallery/example_code_parser.dart';
 import 'package:flutter_test/flutter_test.dart';
@@ -60,9 +58,4 @@ class TestAssetBundle extends AssetBundle {
 
   @override
   String toString() => '$runtimeType@$hashCode()';
-
-  @override
-  Future<T> loadStructuredBinaryData<T>(String key, FutureOr<T> Function(ByteData data) parser) async {
-    return parser(await load(key));
-  }
 }