await in frog: partial support for try-catch blocks

frog/world.dart

 // Copyright (c) 2011, 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.
 
 /** The one true [World]. */
 World world;
 
 /**
  * Experimental phase to enable await, only set when using the
  * await/awaitc.dart entrypoint.
@@ skipping 399 matching lines @@
     process();
     return library;
   }
 
   resolveAll() {
     for (var lib in libraries.getValues()) {
       lib.resolve();
     }
   }
 
-  generateCode(Library lib) {
+  findMainMethod(Library lib) {
     var mainMembers = lib.topType.resolveMember('main');
     var main = null;
     if (mainMembers == null || mainMembers.members.length == 0) {
       fatal('no main method specified');
     } else if (mainMembers.members.length > 1) {
       for (var m in mainMembers.members) {
         main = m;
         error('more than one main member (using last?)', main.span);
       }
     } else {
       main = mainMembers.members[0];
     }
+    return main;
+  }
 
+  generateCode(Library lib) {
     var codeWriter = new CodeWriter();
-    gen = new WorldGenerator(main, codeWriter);
+    gen = new WorldGenerator(findMainMethod(lib), codeWriter);
     gen.run();
     jsBytesWritten = codeWriter.text.length;
   }
 
   // ********************** Message support ***********************
 
   void _message(String color, String prefix, String message,
       SourceSpan span, SourceSpan span1, SourceSpan span2, bool throwing) {
     if (messageHandler != null) {
       // TODO(jimhug): Multiple spans cleaner...
@@ skipping 104 matching lines @@
 
   withTiming(String name, f()) {
     final sw = new Stopwatch();
     sw.start();
     var result = f();
     sw.stop();
     info('$name in ${sw.elapsedInMs()}msec');
     return result;
   }
 }