Add bsdiff package that implements binary diff/patch algorithm.

packages/multicast_dns/lib/src/native_protocol_client.dart

@@ -42,7 +42,7 @@ class ResourceRecordCache {
     // Clear the cache for all name/type combinations to be updated.
     final Map<int, Set<String>> seenRecordTypes = <int, Set<String>>{};
     for (ResourceRecord record in records) {
-      seenRecordTypes[record.resourceRecordType] ??= Set<String>();
+      seenRecordTypes[record.resourceRecordType] ??= {};
       if (seenRecordTypes[record.resourceRecordType].add(record.name)) {
         _cache[record.resourceRecordType] ??=
             SplayTreeMap<String, List<ResourceRecord>>();

packages/palette_generator/lib/palette_generator.dart

@@ -277,7 +277,7 @@ class PaletteGenerator extends Diagnosticable {
   void _selectSwatches() {
     final Set<PaletteTarget> allTargets = Set<PaletteTarget>.from(
         (targets ?? <PaletteTarget>[]) + PaletteTarget.baseTargets);
-    final Set<Color> usedColors = Set<Color>();
+    final Set<Color> usedColors = {};
     for (PaletteTarget target in allTargets) {
       target._normalizeWeights();
       selectedSwatches[target] = _generateScoredTarget(target, usedColors);

third_party/packages/bsdiff/CHANGELOG.md

@@ -0,0 +1,3 @@
+## 0.1.0
+
+* Initial Open Source release.

third_party/packages/bsdiff/LICENSE

@@ -0,0 +1,23 @@
+Copyright 2003-2005 Colin Percival. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+
+1. Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+2. Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.

third_party/packages/bsdiff/README.md

@@ -0,0 +1,29 @@
+# BSDiff
+
+[![pub package](https://img.shields.io/pub/v/bsdiff.svg)](
+https://pub.dartlang.org/packages/bsdiff)
+
+Binary diff/patch algorithm based on
+[bsdiff 4.3](http://www.daemonology.net/bsdiff/) by Colin Percival.
+It's very effective at compressesing incremental changes in binaries.
+
+This implementation has the following differences from Colin's code,
+to make it easier to read and apply patches in Java and Objective C:
+
+* Using gzip instead of bzip2 because gzip is included in JDK by default
+* Using big- instead of little-endian serialization to simplify Java code
+* Using two's complement instead of high-bit coding for negatives numbers
+
+## Usage
+To use this package, add `bsdiff` as a
+[dependency in your pubspec.yaml file](https://flutter.io/platform-plugins/).
+
+## Example
+
+Import the library via
+``` dart
+import 'package:bsdiff/bsdiff.dart';
+```
+
+Then use the `bsdiff` and `bspatch` Dart functions in your code. To see how this is done,
+check out the [example app](example/main.dart).

third_party/packages/bsdiff/example/main.dart

@@ -0,0 +1,23 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Example script to illustrate how to use the bsdiff package to generate and apply patches.
+
+import 'dart:typed_data';
+
+import 'package:bsdiff/bsdiff.dart';
+
+void main() async {
+  final Uint8List originalData = Uint8List.fromList(List.generate(1000, (index) => index));
+  final Uint8List modifiedData = Uint8List.fromList(List.generate(2000, (index) => 2 * index));
+
+  print('Original data size ${originalData.length} bytes');
+  print('Modified data size ${modifiedData.length} bytes');
+
+  final Uint8List generatedPatch = bsdiff(originalData, modifiedData);
+  final Uint8List restoredData = bspatch(originalData, generatedPatch);
+
+  print('Generated patch is ${generatedPatch.length} bytes');
+  print('Restored data size ${restoredData.length} bytes');
+}

third_party/packages/bsdiff/example/pubspec.yaml

@@ -0,0 +1,10 @@
+name: main
+description: A simple example of how to use bsdiff to generate and apply patches.
+version: 0.1.0
+
+dependencies:
+  bsdiff:
+    path: ..
+
+environment:
+  sdk: ">=2.1.1-dev.2.0 <3.0.0"