Dart 2 fixes. (flutter#97)

Bumped version number since the change to RpcClient.invoke is a breaking change.

CHANGELOG.md

@@ -1,3 +1,9 @@
+## 0.8.0
+
+* Breaking change: Added generics to RpcClient.invoke(). Proto files must be
+  rebuilt using Dart protoc_plugin version 0.8.0 or newer to match.
+* Dart 2 fixes.
+
 ## 0.7.2+1
 
 - Updated SDK version to 2.0.0-dev.17.0

lib/src/protobuf/field_set.dart

@@ -129,7 +129,7 @@ class _FieldSet {
 
   List<T> _getDefaultList<T>(FieldInfo<T> fi) {
     assert(fi.isRepeated);
-    if (_isReadOnly) return const [];
+    if (_isReadOnly) return new List.unmodifiable(const []);
 
     // TODO(skybrian) we could avoid this by generating another
     // method for repeated fields:

lib/src/protobuf/rpc_client.dart

@@ -24,10 +24,10 @@ abstract class RpcClient {
   /// The implementation should serialize the request as binary or JSON, as
   /// appropriate. It should merge the reply into [emptyResponse] and
   /// return it.
-  Future<GeneratedMessage> invoke(
+  Future<T> invoke<T extends GeneratedMessage>(
       ClientContext ctx,
       String serviceName,
       String methodName,
       GeneratedMessage request,
-      GeneratedMessage emptyResponse);
+      T emptyResponse);
 }

pubspec.yaml

@@ -1,5 +1,5 @@
 name: protobuf
-version: 0.7.2+1
+version: 0.8.0
 author: Dart Team <misc@dartlang.org>
 description: Runtime library for protocol buffers support.
 homepage: https://github.com/dart-lang/protobuf

test/mock_util.dart

@@ -13,7 +13,7 @@ BuilderInfo mockInfo(String className, CreateBuilderFunc create) {
     ..a(1, "val", PbFieldType.O3, 42)
     ..a(2, "str", PbFieldType.OS)
     ..a(3, "child", PbFieldType.OM, create, create)
-    ..p(4, "int32s", PbFieldType.P3)
+    ..p<int>(4, "int32s", PbFieldType.P3)
     ..a(5, "int64", PbFieldType.O6);
 }
 
@@ -31,7 +31,7 @@ abstract class MockMessage extends GeneratedMessage {
   MockMessage get child => $_getN(2);
   set child(x) => setField(3, x);
 
-  List<int> get int32s => $_getN(3);
+  List<int> get int32s => $_getList(3);
 
   Int64 get int64 => $_get(4, new Int64(0));
   set int64(x) => setField(5, x);