Bump analyzer to 0.27.4.

R=nweiz@google.com

Review URL: https://codereview.chromium.org//2194373002 .
diff --git a/CHANGELOG.md b/CHANGELOG.md
index fcccee8..78e98bd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+# 0.2.9
+
+* Require analyzer 0.27.4, which makes trailing commas on by default.
+
 # 0.2.8
 
 * Format parameter lists with trailing commas like argument lists (#447).
diff --git a/lib/src/dart_formatter.dart b/lib/src/dart_formatter.dart
index 4f5af4e..73df998 100644
--- a/lib/src/dart_formatter.dart
+++ b/lib/src/dart_formatter.dart
@@ -103,8 +103,6 @@
     // Parse it.
     var parser = new Parser(stringSource, errorListener);
 
-    parser.parseTrailingCommas = true;
-
     var node;
     if (source.isCompilationUnit) {
       node = parser.parseCompilationUnit(startToken);
diff --git a/pubspec.lock b/pubspec.lock
index f881840..ed58799 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -6,7 +6,7 @@
       name: analyzer
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.27.4-alpha.17"
+    version: "0.27.4"
   ansicolor:
     description:
       name: ansicolor
@@ -18,7 +18,7 @@
       name: args
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.13.4+2"
+    version: "0.13.5"
   async:
     description:
       name: async
@@ -96,7 +96,7 @@
       name: html
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.12.2+2"
+    version: "0.13.0"
   http:
     description:
       name: http
@@ -162,7 +162,13 @@
       name: package_config
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.1.5"
+    version: "1.0.0"
+  package_resolver:
+    description:
+      name: package_resolver
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.0.0"
   path:
     description:
       name: path
@@ -216,7 +222,7 @@
       name: source_map_stack_trace
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.0.4"
+    version: "1.1.2"
   source_maps:
     description:
       name: source_maps
diff --git a/pubspec.yaml b/pubspec.yaml
index 9464315..1dca374 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,17 +1,16 @@
 name: dart_style
 # Note: See tool/grind.dart for how to bump the version.
-version: 0.2.8
+version: 0.2.9
 author: Dart Team <misc@dartlang.org>
 description: Opinionated, automatic Dart source code formatter.
 homepage: https://github.com/dart-lang/dart_style
 environment:
   sdk: ">=1.8.0 <2.0.0"
 dependencies:
-  analyzer: '^0.27.4-alpha.17'
+  analyzer: '^0.27.4'
   args: '>=0.12.1 <0.14.0'
   path: '>=1.0.0 <2.0.0'
   source_span: '>=1.1.1 <2.0.0'
-
 dev_dependencies:
   async: '>=1.0.0 <=2.0.0'
   browser: '>=0.10.0 <0.11.0'