feat(dart/transform): Simplify dependency imports

Store dependency import information in a dedicated list in `NgDepsModel`
rather than as a boolean field on `ImportModel`. An `ImportModel` should
not "care" whether it is a .ng_deps.dart import or not -- this
information belongs in `NgDepsModel`.

This simplifies some of the logic around how `NgDepsModel` imports are
processed and eventually output.

modules_dart/transform/lib/src/transform/common/code/ng_deps_code.dart

@@ -157,6 +157,7 @@ abstract class NgDepsWriterMixin
     // deferred. Instead `DeferredRewriter` will rewrite the code as to load
     // `ng_deps` in a deferred way.
     model.imports.where((i) => !i.isDeferred).forEach(writeImportModel);
+    model.depImports.where((i) => !i.isDeferred).forEach(writeImportModel);
 
     writeExportModel(new ExportModel()..uri = model.sourceFile);
     model.exports.forEach(writeExportModel);
@@ -202,12 +203,10 @@ abstract class NgDepsWriterMixin
       buffer.writeln(';');
     }
 
-    // Call the setup method for our imports that are `.ng_deps` imports.
-    for (var importModel in model.imports) {
-      if (importModel.isNgDeps) {
+    // Call the setup method for our dependencies.
+    for (var importModel in model.depImports) {
       buffer.writeln('${importModel.prefix}.${SETUP_METHOD_NAME}();');
     }
-    }
 
     buffer.writeln('}');
   }

modules_dart/transform/lib/src/transform/common/model/import_export_model.pb.dart

@@ -11,8 +11,7 @@ class ImportModel extends GeneratedMessage {
     ..p(2, 'showCombinators', PbFieldType.PS)
     ..p(3, 'hideCombinators', PbFieldType.PS)
     ..a(4, 'prefix', PbFieldType.OS)
-    ..a(5, 'isDeferred', PbFieldType.OB)
-    ..a(6, 'isNgDeps', PbFieldType.OB);
+    ..a(5, 'isDeferred', PbFieldType.OB);
 
   ImportModel() : super();
   ImportModel.fromBuffer(List<int> i,
@@ -62,14 +61,6 @@ class ImportModel extends GeneratedMessage {
 
   bool hasIsDeferred() => $_has(4, 5);
   void clearIsDeferred() => clearField(5);
-
-  bool get isNgDeps => $_get(5, 6, false);
-  void set isNgDeps(bool v) {
-    $_setBool(5, 6, v);
-  }
-
-  bool hasIsNgDeps() => $_has(5, 6);
-  void clearIsNgDeps() => clearField(6);
 }
 
 class _ReadonlyImportModel extends ImportModel with ReadonlyMessageMixin {}
@@ -124,7 +115,6 @@ const ImportModel$json = const {
     const {'1': 'hide_combinators', '3': 3, '4': 3, '5': 9},
     const {'1': 'prefix', '3': 4, '4': 1, '5': 9},
     const {'1': 'is_deferred', '3': 5, '4': 1, '5': 8},
-    const {'1': 'is_ng_deps', '3': 6, '4': 1, '5': 8},
   ],
 };
 
@@ -139,7 +129,7 @@ const ExportModel$json = const {
 
 /**
  * Generated with:
- * import_export_model.proto (c018d2ad92db2d341631d813ace70925d1ccbb9b)
+ * import_export_model.proto (36a3a72d0884b84b451b7188ffa1fc93b44e7b62)
  * libprotoc 2.6.1
  * dart-protoc-plugin (af5fc2bf1de367a434c3b1847ab260510878ffc0)
  */

modules_dart/transform/lib/src/transform/common/model/import_export_model.proto

@@ -16,8 +16,6 @@ message ImportModel {
   optional string prefix = 4;
 
   optional bool is_deferred = 5;
-
-  optional bool is_ng_deps = 6;
 }
 
 // See message above about wire-compatiblity with `ImportModel`.

modules_dart/transform/lib/src/transform/common/model/ng_deps_model.pb.dart

@@ -20,7 +20,9 @@ class NgDepsModel extends GeneratedMessage {
     ..a(6, 'sourceFile', PbFieldType.OS)
     ..p(7, 'getters', PbFieldType.PS)
     ..p(8, 'setters', PbFieldType.PS)
-    ..p(9, 'methods', PbFieldType.PS);
+    ..p(9, 'methods', PbFieldType.PS)
+    ..pp(10, 'depImports', PbFieldType.PM, ImportModel.$checkItem,
+        ImportModel.create);
 
   NgDepsModel() : super();
   NgDepsModel.fromBuffer(List<int> i,
@@ -72,6 +74,8 @@ class NgDepsModel extends GeneratedMessage {
   List<String> get setters => $_get(7, 8, null);
 
   List<String> get methods => $_get(8, 9, null);
+
+  List<ImportModel> get depImports => $_get(9, 10, null);
 }
 
 class _ReadonlyNgDepsModel extends NgDepsModel with ReadonlyMessageMixin {}
@@ -106,12 +110,19 @@ const NgDepsModel$json = const {
     const {'1': 'getters', '3': 7, '4': 3, '5': 9},
     const {'1': 'setters', '3': 8, '4': 3, '5': 9},
     const {'1': 'methods', '3': 9, '4': 3, '5': 9},
+    const {
+      '1': 'dep_imports',
+      '3': 10,
+      '4': 3,
+      '5': 11,
+      '6': '.angular2.src.transform.common.model.proto.ImportModel'
+    },
   ],
 };
 
 /**
  * Generated with:
- * ng_deps_model.proto (ab93a7f3c411be8a6dafe914f8aae56027e1bac6)
+ * ng_deps_model.proto (64702efcc1d7fb434f3652943ba051104960ffd5)
  * libprotoc 2.6.1
  * dart-protoc-plugin (af5fc2bf1de367a434c3b1847ab260510878ffc0)
  */

modules_dart/transform/lib/src/transform/common/model/ng_deps_model.proto

@@ -32,4 +32,8 @@ message NgDepsModel {
   // The names of methods that should be registered in the Angular 2 reflection
   // framework.
   repeated string methods = 9;
+
+  // Imports for the .ng_deps.dart files associated with the declared `imports`
+  // and `exports` for this file.
+  repeated ImportModel dep_imports = 10;
 }

modules_dart/transform/lib/src/transform/directive_metadata_linker/ng_deps_linker.dart

@@ -15,10 +15,10 @@ import 'package:barback/barback.dart';
 /// dependencies' associated `.ng_deps.dart` files.
 ///
 /// For example, if entry_point.ng_deps.dart imports dependency.dart, this
-/// will check if dependency.ng_meta.json exists. If it does, we add an import
-/// to dependency.ng_deps.dart to the entry_point [NgDepsModel] and set
-/// `isNgDeps` to `true` to signify that it is a dependency on which we need to
-/// call `initReflector`.
+/// will check if dependency.ng_meta.json exists. If it does, we add an entry
+/// to the `depImports` of [NgDepsModel] for dependency.ng_deps.dart. We can
+/// use this information later to ensure that each file's dependencies are
+/// initialized when that file is initialized.
 Future<NgDepsModel> linkNgDeps(NgDepsModel ngDepsModel, AssetReader reader,
     AssetId assetId, UrlResolver resolver) async {
   if (ngDepsModel == null) return null;
@@ -34,28 +34,16 @@ Future<NgDepsModel> linkNgDeps(NgDepsModel ngDepsModel, AssetReader reader,
     }
 
     final seen = new Set<String>();
-    for (var i = ngDepsModel.imports.length - 1; i >= 0; --i) {
-      var import = ngDepsModel.imports[i];
-      if (linkedDepsMap.containsKey(import.uri) && !seen.contains(import.uri)) {
-        seen.add(import.uri);
+    var idx = 0;
+    final allDeps = [ngDepsModel.imports, ngDepsModel.exports].expand((e) => e);
+    for (var dep in allDeps) {
+      if (linkedDepsMap.containsKey(dep.uri) && !seen.contains(dep.uri)) {
+        seen.add(dep.uri);
         var linkedModel = new ImportModel()
-          ..isNgDeps = true
-          ..uri = toDepsExtension(import.uri)
-          ..prefix = 'i$i';
+          ..uri = toDepsExtension(dep.uri)
+          ..prefix = 'i${idx++}';
         // TODO(kegluneq): Preserve combinators?
-        ngDepsModel.imports.insert(i + 1, linkedModel);
-      }
-    }
-    for (var i = 0, iLen = ngDepsModel.exports.length; i < iLen; ++i) {
-      var export = ngDepsModel.exports[i];
-      if (linkedDepsMap.containsKey(export.uri) && !seen.contains(export.uri)) {
-        seen.add(export.uri);
-        var linkedModel = new ImportModel()
-          ..isNgDeps = true
-          ..uri = toDepsExtension(export.uri)
-          ..prefix = 'i${ngDepsModel.imports.length}';
-        // TODO(kegluneq): Preserve combinators?
-        ngDepsModel.imports.add(linkedModel);
+        ngDepsModel.depImports.add(linkedModel);
       }
     }
     return ngDepsModel;

modules_dart/transform/lib/src/transform/template_compiler/compile_data_creator.dart

@@ -22,7 +22,8 @@ import 'package:barback/barback.dart';
 Future<CompileDataResults> createCompileData(
     AssetReader reader, AssetId assetId, List<String> ambientDirectives) async {
   return logElapsedAsync(() async {
-    final creator = await _CompileDataCreator.create(reader, assetId, ambientDirectives);
+    final creator =
+        await _CompileDataCreator.create(reader, assetId, ambientDirectives);
     return creator != null ? creator.createCompileData() : null;
   }, operationName: 'createCompileData', assetId: assetId);
 }
@@ -43,10 +44,11 @@ class _CompileDataCreator {
   final NgMeta ngMeta;
   final List<String> ambientDirectives;
 
-  _CompileDataCreator(this.reader, this.entryPoint, this.ngMeta, this.ambientDirectives);
+  _CompileDataCreator(
+      this.reader, this.entryPoint, this.ngMeta, this.ambientDirectives);
 
-  static Future<_CompileDataCreator> create(
-      AssetReader reader, AssetId assetId, List<String> ambientDirectives) async {
+  static Future<_CompileDataCreator> create(AssetReader reader, AssetId assetId,
+      List<String> ambientDirectives) async {
     if (!(await reader.hasInput(assetId))) return null;
     final json = await reader.readAsString(assetId);
     if (json == null || json.isEmpty) return null;
@@ -119,7 +121,8 @@ class _CompileDataCreator {
     return res;
   }
 
-  Future<List<CompileDirectiveMetadata>> _readAmbientDirectivesFromUri(String uri, String token) async {
+  Future<List<CompileDirectiveMetadata>> _readAmbientDirectivesFromUri(
+      String uri, String token) async {
     final metaAssetId = fromUri(toMetaExtension(uri));
     if (await reader.hasInput(metaAssetId)) {
       try {
@@ -129,19 +132,16 @@ class _CompileDataCreator {
 
           if (newMetadata.types.containsKey(token)) {
             return [newMetadata.types[token]];
-
           } else if (newMetadata.aliases.containsKey(token)) {
             return newMetadata.flatten(token);
-
           } else {
-            log.warning('Could not resolve ambient directive ${token} in ${uri}',
+            log.warning(
+                'Could not resolve ambient directive ${token} in ${uri}',
                 asset: metaAssetId);
           }
-
         }
       } catch (ex, stackTrace) {
-        log.warning('Failed to decode: $ex, $stackTrace',
-            asset: metaAssetId);
+        log.warning('Failed to decode: $ex, $stackTrace', asset: metaAssetId);
       }
     }
     return [];
@@ -160,7 +160,7 @@ class _CompileDataCreator {
     final resolver = const TransformerUrlResolver();
 
     ngMeta.ngDeps.imports
-        .where((model) => !model.isNgDeps && !isDartCoreUri(model.uri))
+        .where((model) => !isDartCoreUri(model.uri))
         .forEach((model) {
       var prefix = model.prefix == null ? '' : model.prefix;
       map