Move native and js interop properties from the element model to the JS backend

pkg/compiler/lib/src/ssa/codegen.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 ssa;
 
 class SsaCodeGeneratorTask extends CompilerTask {
 
   final JavaScriptBackend backend;
   final SourceInformationStrategy sourceInformationFactory;
@@ skipping 1530 matching lines @@
     if (target != null && !node.isInterceptedCall) {
       if (target == backend.jsArrayAdd) {
         methodName = 'push';
       } else if (target == backend.jsArrayRemoveLast) {
         methodName = 'pop';
       } else if (target == backend.jsStringSplit) {
         methodName = 'split';
         // Split returns a List, so we make sure the backend knows the
         // list class is instantiated.
         registry.registerInstantiatedClass(compiler.listClass);
-      } else if (target.isNative && target.isFunction
+      } else if (backend.isNative(target) && target.isFunction
                  && !node.isInterceptedCall) {
         // A direct (i.e. non-interceptor) native call is the result of
         // optimization.  The optimization ensures any type checks or
         // conversions have been satisified.
-        methodName = target.fixedBackendName;
+        methodName = backend.getFixedBackendName(target);
       }
     }
 
     js.Name methodLiteral;
     if (methodName == null) {
       methodLiteral = backend.namer.invocationName(node.selector);
       registerMethodInvoke(node);
     } else {
       methodLiteral = backend.namer.asName(methodName);
     }
@@ skipping 1313 matching lines @@
     }
     registry.registerStaticUse(helper);
     return backend.emitter.staticFunctionAccess(helper);
   }
 
   @override
   void visitRef(HRef node) {
     visit(node.value);
   }
 }