Implement modular compilation

lib/src/compiler/js_typeref_codegen.dart

Index: lib/src/compiler/js_typeref_codegen.dart
diff --git a/lib/src/codegen/js_typeref_codegen.dart b/lib/src/compiler/js_typeref_codegen.dart
similarity index 82%
rename from lib/src/codegen/js_typeref_codegen.dart
rename to lib/src/compiler/js_typeref_codegen.dart
index 7aa4c0a2e7d0786aef798846670d9a045c99ad7c..b43692d09b699aff46e20be3de8e47248b99a06f 100644
--- a/lib/src/codegen/js_typeref_codegen.dart
+++ b/lib/src/compiler/js_typeref_codegen.dart
@@ -7,8 +7,8 @@ import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/generated/resolver.dart' show TypeProvider;
 import 'package:analyzer/src/generated/utilities_dart.dart';
 
-import '../js/js_ast.dart' as JS;
-import '../options.dart';
+import '../js_ast/js_ast.dart' as JS;
+import 'compiler.dart' show CompilerOptions;
 import 'js_interop.dart';
 
 /// Mixin with logic to generate [TypeRef]s out of [DartType]s.
@@ -16,23 +16,17 @@ abstract class JsTypeRefCodegen {
   final _resolved = <DartType, JS.TypeRef>{};
 
   // Mixin dependencies:
-  CodegenOptions get options;
+  CompilerOptions get options;
   TypeProvider get types;
+  LibraryElement get dartJSLibrary;
   JS.Identifier get namedArgumentTemp;
-  LibraryElement get currentLibrary;
   JS.Identifier emitLibraryName(LibraryElement e);
 
   /// Finds the qualified path to the type.
   JS.TypeRef _emitTopLevelTypeRef(DartType type) {
     var e = type.element;
-    if (e.library == currentLibrary) {
-      return new JS.TypeRef.named(type.name);
-    } else {
-      return new JS.TypeRef.qualified([
-        emitLibraryName(e.library),
-        new JS.Identifier(getJSExportName(e, types) ?? type.name)
-      ]);
-    }
+    return new JS.TypeRef.qualified(
+        [emitLibraryName(e.library), new JS.Identifier(getJSExportName(e))]);
   }
 
   JS.TypeRef emitTypeRef(DartType type) {
@@ -114,20 +108,18 @@ abstract class JsTypeRefCodegen {
   /// Special treatment of types from dart:js
   /// TODO(ochafik): Is this the right thing to do? And what about package:js?
   JS.TypeRef _getDartJsTypeRef(DartType type) {
-    switch (type.element.source.uri.toString()) {
-      case 'dart:js':
-        switch (type.name) {
-          case 'JsArray':
-            return new JS.TypeRef.array(
-                type is InterfaceType && type.typeArguments.length == 1
-                    ? emitTypeRef(type.typeArguments.single)
-                    : null);
-          case 'JsObject':
-            return new JS.TypeRef.object();
-          case 'JsFunction':
-            return new JS.TypeRef.function();
-        }
-        break;
+    if (type.element.library == dartJSLibrary) {
+      switch (type.name) {
+        case 'JsArray':
+          return new JS.TypeRef.array(
+              type is InterfaceType && type.typeArguments.length == 1
+                  ? emitTypeRef(type.typeArguments.single)
+                  : null);
+        case 'JsObject':
+          return new JS.TypeRef.object();
+        case 'JsFunction':
+          return new JS.TypeRef.function();
+      }
     }
     return null;
   }