Add @jsify annotation. Support automatically proxying Lists and Maps to Dart in Proxies. Support co…

test_sources/non_transformed/lib/library.js

Index: test_sources/non_transformed/lib/library.js
diff --git a/test_sources/non_transformed/lib/library.js b/test_sources/non_transformed/lib/library.js
index 737a119e941fdbec0362f560b26a9f191cd13df1..2989b11e0e960f7d35401910b1355188262519fd 100644
--- a/test_sources/non_transformed/lib/library.js
+++ b/test_sources/non_transformed/lib/library.js
@@ -26,6 +26,10 @@ JsThing.prototype.setBar = function(bar) {
   this.bar = bar;
 }
 
+JsThing.prototype.toString = function() {
+  return this.name;
+}
+
 function JsThing2(name) {
   this.name = name;
   this.y = 42;