refactor(injector): uses one instance of reflector instead of creating a new instance every time

modules/di/src/binding.js

@@ -1,6 +1,6 @@
 import {Type, bool} from 'facade/lang';
 import {List, MapWrapper, ListWrapper} from 'facade/collection';
-import {Reflector} from './reflector';
+import {reflector} from './reflector';
 import {Key, Dependency} from './key';
 
 export class Binding {
@@ -19,14 +19,13 @@ export function bind(token):BindingBuilder {
 export class BindingBuilder {
   constructor(token) {
     this.token = token;
-    this.reflector = new Reflector();
   }
 
   toClass(type:Type):Binding {
     return new Binding(
       Key.get(this.token),
-      this.reflector.factoryFor(type),
-      this.reflector.dependencies(type),
+      reflector.factoryFor(type),
+      reflector.dependencies(type),
       false
     );
   }
@@ -43,7 +42,7 @@ export class BindingBuilder {
   toFactory(dependencies:List, factoryFunction:Function):Binding {
     return new Binding(
       Key.get(this.token),
-      this.reflector.convertToFactory(factoryFunction),
+      reflector.convertToFactory(factoryFunction),
       this._constructDependencies(dependencies),
       false
     );
@@ -52,7 +51,7 @@ export class BindingBuilder {
   toAsyncFactory(dependencies:List, factoryFunction:Function):Binding {
     return new Binding(
       Key.get(this.token),
-      this.reflector.convertToFactory(factoryFunction),
+      reflector.convertToFactory(factoryFunction),
       this._constructDependencies(dependencies),
       true
     );

modules/di/src/reflector.dart

@@ -49,3 +49,5 @@ class Reflector {
     }, growable:false);
   }
 }
+
+final Reflector reflector = new Reflector();

modules/di/src/reflector.es6

@@ -1,18 +1,19 @@
 import {Type, isPresent} from 'facade/lang';
+import {List} from 'facade/collection';
 import {Inject, InjectFuture, InjectLazy} from './annotations';
 import {Dependency, Key} from './key';
 import {NoAnnotationError} from './exceptions';
 
-export class Reflector {
-  factoryFor(type:Type) {
+class Reflector {
+  factoryFor(type:Type):Function {
     return (args) => new type(...args);
   }
 
-  convertToFactory(factoryFunction:Function) {
+  convertToFactory(factoryFunction:Function):Function {
     return (args) => factoryFunction(...args);
   }
 
-  dependencies(type:Type) {
+  dependencies(type:Type):List {
     var p = type.parameters;
     if (p == undefined && type.length == 0) return [];
     if (p == undefined) throw new NoAnnotationError(type);
@@ -48,3 +49,5 @@ export class Reflector {
     return new Dependency(Key.get(token), asFuture, lazy);
   }
 }
+
+export var reflector:Reflector = new Reflector();