Move cassowary into package:flutter (#3591)

Cassowary doesn't have any additional dependencies and this simplifies things.

Fixes #2442

examples/layers/rendering/autolayout.dart

@@ -5,7 +5,7 @@
 // This example shows how to use the Cassowary autolayout system directly in the
 // underlying render tree.
 
-import 'package:cassowary/cassowary.dart' as al;
+import 'package:flutter/cassowary.dart' as al;
 import 'package:flutter/rendering.dart';
 
 class _MyAutoLayoutDelegate extends AutoLayoutDelegate {

examples/layers/widgets/autolayout.dart

@@ -4,7 +4,7 @@
 
 // This example shows how to use the Cassowary autolayout system with widgets.
 
-import 'package:cassowary/cassowary.dart' as al;
+import 'package:flutter/cassowary.dart' as al;
 import 'package:flutter/widgets.dart';
 
 class _MyAutoLayoutDelegate extends AutoLayoutDelegate {

packages/cassowary/lib/cassowary.dart

@@ -1,28 +0,0 @@
-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-/// An implementation of the Cassowary constraint solving algorithm in Dart.
-/// 
-/// This library is not meant to be imported by developers.
-/// It will soon be integrated into another Flutter library.
-///
-/// This is used by the [RenderAutoLayout] render object in the rendering
-/// library and by the [AutoLayout] widget in the widget library.
-///
-/// See also:
-///
-/// * <https://en.wikipedia.org/wiki/Cassowary_(software)>
-/// * <https://constraints.cs.washington.edu/solvers/cassowary-tochi.pdf>
-library cassowary;
-
-export 'src/constraint.dart';
-export 'src/expression.dart';
-export 'src/term.dart';
-export 'src/equation_member.dart';
-export 'src/constant_member.dart';
-export 'src/solver.dart';
-export 'src/result.dart';
-export 'src/parser_exception.dart';
-export 'src/param.dart';
-export 'src/priority.dart';

packages/cassowary/pubspec.yaml

@@ -1,10 +0,0 @@
-name: cassowary
-description: Cassowary Constraint Solving Toolkit
-version: 0.1.7
-author: Flutter Authors <flutter-dev@googlegroups.com>
-homepage: https://github.com/flutter/flutter/tree/master/packages/cassowary
-environment:
-  sdk: '>=1.0.0 <2.0.0'
-dev_dependencies:
-  flutter_test:
-    path: ../flutter_test

packages/cassowary/test/all.dart

@@ -1,9 +0,0 @@
-// Copyright (c) 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-import 'cassowary_test.dart' as cassowary_test;
-
-void main() {
-  cassowary_test.main();
-}

packages/flutter/lib/cassowary.dart

@@ -0,0 +1,27 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/// An implementation of the Cassowary constraint solving algorithm in Dart.
+///
+/// To use, import `package:flutter/cassowary.dart`.
+///
+/// This is used by the [RenderAutoLayout] render object in the rendering
+/// library and by the [AutoLayout] widget in the widget library.
+///
+/// See also:
+///
+/// * <https://en.wikipedia.org/wiki/Cassowary_(software)>
+/// * <https://constraints.cs.washington.edu/solvers/cassowary-tochi.pdf>
+library cassowary;
+
+export 'src/cassowary/constraint.dart';
+export 'src/cassowary/expression.dart';
+export 'src/cassowary/term.dart';
+export 'src/cassowary/equation_member.dart';
+export 'src/cassowary/constant_member.dart';
+export 'src/cassowary/solver.dart';
+export 'src/cassowary/result.dart';
+export 'src/cassowary/parser_exception.dart';
+export 'src/cassowary/param.dart';
+export 'src/cassowary/priority.dart';

packages/flutter/lib/src/cassowary/constant_member.dart

@@ -1,4 +1,4 @@
-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 

packages/flutter/lib/src/cassowary/constraint.dart

@@ -1,4 +1,4 @@
-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 

packages/flutter/lib/src/cassowary/equation_member.dart

@@ -1,4 +1,4 @@
-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 

packages/flutter/lib/src/cassowary/expression.dart

@@ -1,4 +1,4 @@
-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 

packages/flutter/lib/src/cassowary/param.dart

@@ -1,4 +1,4 @@
-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 

packages/flutter/lib/src/cassowary/parser_exception.dart

@@ -1,4 +1,4 @@
-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 

packages/flutter/lib/src/cassowary/priority.dart

@@ -1,4 +1,4 @@
-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 

packages/flutter/lib/src/cassowary/result.dart

@@ -1,4 +1,4 @@
-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 

packages/flutter/lib/src/cassowary/solver.dart

@@ -1,4 +1,4 @@
-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 

packages/flutter/lib/src/cassowary/term.dart

@@ -1,4 +1,4 @@
-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 

packages/flutter/lib/src/rendering/auto_layout.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:cassowary/cassowary.dart' as al; // "auto layout"
+import 'package:flutter/cassowary.dart' as al; // "auto layout"
 
 import 'box.dart';
 import 'object.dart';

packages/flutter/pubspec.yaml

@@ -19,9 +19,6 @@ dependencies:
   sky_services:
     path: ../../bin/cache/pkg/sky_services
 
-  cassowary:
-    path: ../cassowary
-
 dev_dependencies:
   flutter_test:
     path: ../flutter_test

packages/flutter/test/cassowary/cassowary_test.dart

@@ -1,10 +1,10 @@
-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 import 'package:test/test.dart';
 
-import 'package:cassowary/cassowary.dart';
+import 'package:flutter/cassowary.dart';
 
 void main() {
   test('variable', () {

travis/test.sh

@@ -10,7 +10,6 @@ flutter analyze --flutter-repo
 # //chrome_infra/build/scripts/slave/recipes/flutter/flutter.py
 # see https://github.com/flutter/flutter/blob/master/infra/README.md
 
-(cd packages/cassowary; dart -c test/all.dart)
 (cd packages/flutter; flutter test)
 (cd packages/flutter_driver; dart -c test/all.dart)
 (cd packages/flutter_sprites; flutter test)