Implement reflection on function type aliases (typedef).

dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of js_backend;
 
 /**
  * A function element that represents a closure call. The signature is copied
  * from the given element.
  */
@@ skipping 3674 matching lines @@
         for (; !link.isEmpty; link = link.tail) {
           metadata.add(reifyMetadata(link.head));
         }
       }
       code.body.statements.add(js.string(metadata.join(',')).toStatement());
       return code;
     });
   }
 
   void emitMetadata(CodeBuffer buffer) {
-    buffer.write('init.metadata$_=$_[');
+    var literals = backend.typedefTypeLiterals.toList();
+    Elements.sortedByPosition(literals);
+    var properties = [];
+    for (TypedefElement literal in literals) {
+      var key = namer.getName(literal);
+      var value = js.toExpression(reifyType(literal.rawType));
+      properties.add(new jsAst.Property(js.string(key), value));
+    }
+    var map = new jsAst.ObjectInitializer(properties);
+    buffer.write(
+        jsAst.prettyPrint(
+            js('init.functionAliases = #', map).toStatement(), compiler));
+    buffer.write('${N}init.metadata$_=$_[');
     for (var metadata in globalMetadata) {
       if (metadata is String) {
         if (metadata != 'null') {
           buffer.write(metadata);
         }
       } else {
         throw 'Unexpected value in metadata: ${Error.safeToString(metadata)}';
       }
       buffer.write(',$n');
     }
@@ skipping 483 matching lines @@
 
 const String HOOKS_API_USAGE = """
 // The code supports the following hooks:
 // dartPrint(message)   - if this function is defined it is called
 //                        instead of the Dart [print] method.
 // dartMainRunner(main) - if this function is defined, the Dart [main]
 //                        method will not be invoked directly.
 //                        Instead, a closure that will invoke [main] is
 //                        passed to [dartMainRunner].
 """;