Adding Angular and dependent packages for testing

third_party/pkg/angular/lib/core/registry.dart

+part of angular.core;
+
+abstract class AnnotationMap<K> {
+  final Map<K, Type> _map = {};
+
+  AnnotationMap(Injector injector, MetadataExtractor extractMetadata) {
+    injector.types.forEach((type) {
+      var meta = extractMetadata(type)
+        .where((annotation) => annotation is K)
+        .forEach((annotation) {
+          if (_map.containsKey(annotation)) {
+            var annotationType = K;
+            throw "Duplicate annotation found: $annotationType: $annotation. " +
+                  "Exisitng: ${_map[annotation]}; New: $type.";
+          }
+          _map[annotation] = type;
+        });
+    });
+  }
+
+  Type operator[](K annotation) {
+    var value = _map[annotation];
+    if (value == null) {
+      throw 'No $annotation found!';
+    }
+    return value;
+  }
+
+  forEach(fn(K, Type)) => _map.forEach(fn);
+
+  List<K> annotationsFor(Type type) {
+    var res = <K>[];
+    forEach((ann, annType) {
+      if (annType == type) {
+        res.add(ann);
+      }
+    });
+    return res;
+  }
+}
+
+@NgInjectableService()
+class MetadataExtractor {
+
+  Iterable call(Type type) {
+    var metadata = reflectClass(type).metadata;
+    if (metadata == null) return [];
+    return metadata.map((InstanceMirror im) => im.reflectee);
+  }
+}