fix(transformer): Fixing some analyzer warnings

A couple appear to have crept in, found when integrating into Dart's repo.

Closes #955

Author: Pete Blois

lib/tools/transformer/metadata_extractor.dart

@@ -10,7 +10,7 @@ import 'package:code_transformers/resolver.dart';
 
 class AnnotatedType {
   final ClassElement type;
-  Iterable<Annotation> annotations;
+  List<Annotation> annotations;
 
   AnnotatedType(this.type);
 
@@ -269,19 +269,17 @@ class AnnotationExtractor {
         .where((Annotation annotation) {
           var element = annotation.element;
           if (element != null && !element.isPublic) {
-            warn('Annotation $annotation is not public.',
-                annotation.parent.element);
+            warn('Annotation $annotation is not public.', cls);
             return false;
           }
           if (element is! ConstructorElement) {
             // Only keeping constructor elements.
             return false;
           }
           ConstructorElement ctor = element;
-          var cls = ctor.enclosingElement;
-          if (!cls.isPublic) {
-            warn('Annotation $annotation is not public.',
-                annotation.parent.element);
+          var annotationClass = ctor.enclosingElement;
+          if (!annotationClass.isPublic) {
+            warn('Annotation $annotation is not public.', cls);
             return false;
           }
           return element.enclosingElement.type.isAssignableTo(directiveType.type) ||

lib/tools/transformer/metadata_generator.dart

@@ -1,6 +1,5 @@
 library angular.tools.transformer.metadata_generator;
 
-import 'dart:async';
 import 'package:analyzer/src/generated/element.dart';
 import 'package:angular/tools/transformer/options.dart';
 import 'package:barback/barback.dart';

lib/tools/transformer/options.dart

@@ -1,9 +1,5 @@
 library angular.tools.transformer.options;
 
-import 'dart:async';
-
-import 'package:barback/barback.dart';
-import 'package:code_transformers/resolver.dart';
 import 'package:di/transformer/options.dart' as di;
 
 /** Options used by Angular transformers */

lib/tools/transformer/static_angular_generator.dart

@@ -1,6 +1,5 @@
 library angular.tools.transformer.static_angular_generator;
 
-import 'dart:async';
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
 import 'package:angular/tools/transformer/options.dart';

lib/transformer.dart

@@ -9,7 +9,7 @@ import 'package:angular/tools/transformer/html_dart_references_generator.dart';
 import 'package:angular/tools/transformer/options.dart';
 import 'package:barback/barback.dart';
 import 'package:code_transformers/resolver.dart';
-import 'package:di/transformer/injector_generator.dart' as di;
+import 'package:di/transformer/injector_generator.dart' show InjectorGenerator;
 import 'package:di/transformer/options.dart' as di;
 import 'package:path/path.dart' as path;
 
@@ -126,7 +126,7 @@ List<List<Transformer>> _createPhases(TransformOptions options) {
     [new HtmlDartReferencesGenerator(options)],
     [new _SerialTransformer([
       new ExpressionGenerator(options, resolvers),
-      new di.InjectorGenerator(options.diOptions, resolvers),
+      new InjectorGenerator(options.diOptions, resolvers),
       new MetadataGenerator(options, resolvers),
       new StaticAngularGenerator(options, resolvers)
     ])]
@@ -145,7 +145,7 @@ class _SerialTransformer extends Transformer {
   final Iterable<Transformer> _transformers;
   _SerialTransformer(this._transformers);
 
-  Future<bool> isPrimary(Asset input) =>
+  Future<bool> isPrimary(input) =>
       Future.wait(_transformers.map((t) => t.isPrimary(input)))
           .then((l) => l.any((result) => result));