Initial support for runtime function types and type checking

lib/runtime/dart/_interceptors.js

 var _interceptors;
 (function(exports) {
   'use strict';
   let JSMutableArray$ = dart.generic(function(E) {
     class JSMutableArray extends JSArray$(E) {}
     JSMutableArray[dart.implements] = () => [JSMutableIndexable];
     return JSMutableArray;
   });
   let JSMutableArray = JSMutableArray$();
   let JSFixedArray$ = dart.generic(function(E) {
@@ skipping 854 matching lines @@
     }
   }
   // Function _symbolToString: (Symbol) → String
   function _symbolToString(symbol) {
     return _internal.Symbol.getName(dart.as(symbol, _internal.Symbol));
   }
   // Function _symbolMapToStringMap: (Map<Symbol, dynamic>) → dynamic
   function _symbolMapToStringMap(map) {
     if (map == null)
       return null;
-    let result = new (core.Map$(core.String, dynamic))();
+    let result = new (core.Map$(core.String, dart.dynamic))();
     map.forEach((key, value) => {
       result.set(_symbolToString(key), value);
     });
     return result;
   }
   // Function getInterceptor: (dynamic) → dynamic
   function getInterceptor(object) {
     return void 0;
   }
   // Function getDispatchProperty: (dynamic) → dynamic
@@ skipping 196 matching lines @@
   exports.findInterceptorForType = findInterceptorForType;
   exports.JSBool = JSBool;
   exports.JSNull = JSNull;
   exports.JSIndexable = JSIndexable;
   exports.JSMutableIndexable = JSMutableIndexable;
   exports.JSObject = JSObject;
   exports.JavaScriptObject = JavaScriptObject;
   exports.PlainJavaScriptObject = PlainJavaScriptObject;
   exports.UnknownJavaScriptObject = UnknownJavaScriptObject;
 })(_interceptors || (_interceptors = {}));