Rewire DDC to use the analyzer task model

test/codegen/expect/covariance.js

 dart_library.library('covariance', null, /* Imports */[
   "dart_runtime/dart",
   'dart/core'
 ], /* Lazy imports */[
 ], function(exports, dart, core) {
   'use strict';
   let dartx = dart.dartx;
   let _t = Symbol('_t');
   let Foo$ = dart.generic(function(T) {
     class Foo extends core.Object {
@@ skipping 16 matching lines @@
       })
     });
     return Foo;
   });
   let Foo = Foo$();
   class Bar extends Foo$(core.int) {
     Bar() {
       super.Foo();
     }
     add(x) {
-      core.print(`Bar.add got ${x}`);
-      super.add(x);
+      dart.dcall(core.print, `Bar.add got ${x}`);
+      dart.dcall(super.add, x);
     }
   }
   dart.setSignature(Bar, {
     methods: () => ({add: [dart.dynamic, [core.int]]})
   });
   function main() {
     let foo = new Bar();
-    foo.add('hi');
+    dart.dcall(foo.add, 'hi');
   }
   dart.fn(main);
   // Exports:
   exports.Foo$ = Foo$;
   exports.Foo = Foo;
   exports.Bar = Bar;
   exports.main = main;
 });