Remove upper case constants (dart-lang/stream_channel#17)

* Remove usage of upper-case constants.

* update SDK version
* remove stable from Travis config

pkgs/stream_channel/.travis.yml

diff --git a/pkgs/stream_channel/.travis.yml b/pkgs/stream_channel/.travis.yml
index a951032..45359fb 100644
--- a/pkgs/stream_channel/.travis.yml
+++ b/pkgs/stream_channel/.travis.yml
@@ -2,8 +2,6 @@
 
 dart:
   - dev
-  - stable
-
 dart_task:
   - test: --platform vm
   - test: --platform firefox -j 1

pkgs/stream_channel/CHANGELOG.md

diff --git a/pkgs/stream_channel/CHANGELOG.md b/pkgs/stream_channel/CHANGELOG.md
index 014b2fc..eafdb81 100644
--- a/pkgs/stream_channel/CHANGELOG.md
+++ b/pkgs/stream_channel/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 1.6.7
+
+* Update SDK version to 2.0.0-dev.17.0.
+
 ## 1.6.6
 
 * Fix a Dart 2 issue with inner stream transformation in `GuaranteeChannel`.

pkgs/stream_channel/pubspec.yaml

diff --git a/pkgs/stream_channel/pubspec.yaml b/pkgs/stream_channel/pubspec.yaml
index c121f5f..47e24c2 100644
--- a/pkgs/stream_channel/pubspec.yaml
+++ b/pkgs/stream_channel/pubspec.yaml
@@ -1,10 +1,10 @@
 name: stream_channel
-version: 1.6.6
+version: 1.6.7-dev
 description: An abstraction for two-way communication channels.
 author: Dart Team <misc@dartlang.org>
 homepage: https://github.com/dart-lang/stream_channel
 environment:
-  sdk: '>=1.21.0 <2.0.0'
+  sdk: '>=2.0.0-dev.17.0 <2.0.0'
 dependencies:
   async: '>=1.11.0 <3.0.0'
   stack_trace: '^1.0.0'

pkgs/stream_channel/test/json_document_transformer_test.dart

diff --git a/pkgs/stream_channel/test/json_document_transformer_test.dart b/pkgs/stream_channel/test/json_document_transformer_test.dart
index b55a118..d6fd72b 100644
--- a/pkgs/stream_channel/test/json_document_transformer_test.dart
+++ b/pkgs/stream_channel/test/json_document_transformer_test.dart
@@ -29,7 +29,7 @@
     var transformed = channel.transform(jsonDocument);
     transformed.sink.add({"foo": "bar"});
     expect(sinkController.stream.first,
-        completion(equals(JSON.encode({"foo": "bar"}))));
+        completion(equals(jsonEncode({"foo": "bar"}))));
   });
 
   test("supports the reviver function", () {

pkgs/stream_channel/test/stream_channel_test.dart

diff --git a/pkgs/stream_channel/test/stream_channel_test.dart b/pkgs/stream_channel/test/stream_channel_test.dart
index 4ec84bc..dbe4211 100644
--- a/pkgs/stream_channel/test/stream_channel_test.dart
+++ b/pkgs/stream_channel/test/stream_channel_test.dart
@@ -43,7 +43,7 @@
   test("transform() transforms the channel", () async {
     var transformed = channel
         .cast<List<int>>()
-        .transform(new StreamChannelTransformer.fromCodec(UTF8));
+        .transform(new StreamChannelTransformer.fromCodec(utf8));
 
     streamController.add([102, 111, 111, 98, 97, 114]);
     streamController.close();