feat(dart/transform): Add debug transform parameters

Add two transform parameters to aid in debugging the transformer
- `mirror_mode`, with values {`debug`, `none`, and `verbose`}
- `init_reflector`, with values {`true`, `false`}

`mirror_mode`:
- `debug`: Allow reflective access, but log a message if it is used
- `none`: Remove reflective access, `throw` if it is used. Default value
- `verbose`: Allow reflective access, log a stack trace if it is used

`init_reflector`: Whether to generate calls to our generated
`initReflector` code.

These will be useful to reveal areas where the transformer is not generating
appropriate code and to quickly see where reflective accesses occur.

When the pub mode is `transform_dynamic`, we run in MirrorMode.debug
with `init_reflector = false`. This is used for testing purposes.

modules/angular2/src/transform/common/mirror_mode.dart

@@ -0,0 +1,10 @@
+library angular2.transform.common.mirror_mode;
+
+/// Modes for mirror use.
+/// `none` is the default value and signifies that mirror use should be
+/// removed.
+/// `debug` allows the use of mirrors and logs a notice whenever they are
+/// accessed.
+/// `verbose` allows the use of mirrors and logs a stack trace whenever they
+/// are accessed.
+enum MirrorMode { debug, none, verbose }

modules/angular2/src/transform/common/names.dart

@@ -2,10 +2,10 @@ library angular2.transform.common.names;
 
 const SETUP_METHOD_NAME = 'initReflector';
 const REFLECTOR_VAR_NAME = 'reflector';
+const TRANSFORM_DYNAMIC_MODE = 'transform_dynamic';
 const DEPS_EXTENSION = '.ng_deps.dart';
 const REFLECTION_CAPABILITIES_NAME = 'ReflectionCapabilities';
 const REGISTER_TYPE_METHOD_NAME = 'registerType';
 const REGISTER_GETTERS_METHOD_NAME = 'registerGetters';
 const REGISTER_SETTERS_METHOD_NAME = 'registerSetters';
 const REGISTER_METHODS_METHOD_NAME = 'registerMethods';
-const TRANSFORM_MODE = 'ngstatic';

modules/angular2/src/transform/common/options.dart

@@ -1,5 +1,7 @@
 library angular2.transform.common.options;
 
+import 'mirror_mode.dart';
+
 const ENTRY_POINT_PARAM = 'entry_points';
 const REFLECTION_ENTRY_POINT_PARAM = 'reflection_entry_points';
 
@@ -15,15 +17,22 @@ class TransformerOptions {
   /// The `BarbackMode#name` we are running in.
   final String modeName;
 
-  TransformerOptions._internal(
-      this.entryPoints, this.reflectionEntryPoints, this.modeName);
+  /// The [MirrorMode] to use for the transformation.
+  final MirrorMode mirrorMode;
+
+  /// Whether to generate calls to our generated `initReflector` code
+  final bool initReflector;
+
+  TransformerOptions._internal(this.entryPoints, this.reflectionEntryPoints,
+      this.modeName, this.mirrorMode, this.initReflector);
 
   factory TransformerOptions(List<String> entryPoints,
-      {List<String> reflectionEntryPoints, String modeName: 'release'}) {
+      {List<String> reflectionEntryPoints, String modeName: 'release',
+      MirrorMode mirrorMode: MirrorMode.none, bool initReflector: true}) {
     if (reflectionEntryPoints == null || reflectionEntryPoints.isEmpty) {
       reflectionEntryPoints = entryPoints;
     }
-    return new TransformerOptions._internal(
-        entryPoints, reflectionEntryPoints, modeName);
+    return new TransformerOptions._internal(entryPoints, reflectionEntryPoints,
+        modeName, mirrorMode, initReflector);
   }
 }

modules/angular2/src/transform/common/options_reader.dart

@@ -1,6 +1,7 @@
 library angular2.transform.common.options_reader;
 
 import 'package:barback/barback.dart';
+import 'mirror_mode.dart';
 import 'options.dart';
 
 TransformerOptions parseBarbackSettings(BarbackSettings settings) {
@@ -8,9 +9,27 @@ TransformerOptions parseBarbackSettings(BarbackSettings settings) {
   var entryPoints = _readFileList(config, ENTRY_POINT_PARAM);
   var reflectionEntryPoints =
       _readFileList(config, REFLECTION_ENTRY_POINT_PARAM);
+  var initReflector = !config.containsKey('init_reflector') ||
+      config['init_reflector'] != false;
+  String mirrorModeVal =
+      config.containsKey('mirror_mode') ? config['mirror_mode'] : '';
+  var mirrorMode = MirrorMode.none;
+  switch (mirrorModeVal) {
+    case 'debug':
+      mirrorMode = MirrorMode.debug;
+      break;
+    case 'verbose':
+      mirrorMode = MirrorMode.verbose;
+      break;
+    default:
+      mirrorMode = MirrorMode.none;
+      break;
+  }
   return new TransformerOptions(entryPoints,
       reflectionEntryPoints: reflectionEntryPoints,
-      modeName: settings.mode.name);
+      modeName: settings.mode.name,
+      mirrorMode: mirrorMode,
+      initReflector: initReflector);
 }
 
 /// Cribbed from the polymer project.