dart2js: add function type to the model.

pkg/compiler/lib/src/js_emitter/program_builder.dart

 // Copyright (c) 2014, 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.
 
 library dart2js.js_emitter.program_builder;
 
 import 'js_emitter.dart' show computeMixinClass;
 import 'model.dart';
 
 import '../common.dart';
@@ skipping 526 matching lines @@
     if (element.isGenerativeConstructorBody) {
       // TODO(herhut): Why does this need to be normalized away? We never need
       //               this information anyway as they cannot be torn off or
       //               reflected.
       var body = element;
       memberType = body.constructor.type;
     } else {
       memberType = element.type;
     }
 
+    js.Expression functionType;
+    if (canTearOff || canBeReflected) {
+      functionType = _generateFunctionType(memberType);
+    }
+
     int requiredParameterCount;
     var /* List | Map */ optionalParameterDefaultValues;
     if (canBeApplied || canBeReflected) {
       FunctionSignature signature = element.functionSignature;
       requiredParameterCount = signature.requiredParameterCount;
       optionalParameterDefaultValues =
           _computeParameterDefaultValues(signature);
     }
 
     return new InstanceMethod(element, name, code,
-        _generateParameterStubs(element, canTearOff), callName, memberType,
+        _generateParameterStubs(element, canTearOff), callName,
         needsTearOff: canTearOff, tearOffName: tearOffName,
         isClosure: isClosure, aliasName: aliasName,
         canBeApplied: canBeApplied, canBeReflected: canBeReflected,
         requiredParameterCount: requiredParameterCount,
-        optionalParameterDefaultValues: optionalParameterDefaultValues);
+        optionalParameterDefaultValues: optionalParameterDefaultValues,
+        functionType: functionType);
+  }
+
+  js.Expression _generateFunctionType(DartType type) {
+    if (type.containsTypeVariables) {
+      js.Expression thisAccess = js.js(r'this.$receiver');
+      return backend.rti.getSignatureEncoding(type, thisAccess);
+    } else {
+      return js.number(backend.emitter.metadataCollector.reifyType(type));
+    }
   }
 
   List<ParameterStubMethod> _generateParameterStubs(FunctionElement element,
                                                     bool canTearOff) {
 
     if (!_methodNeedsStubs(element)) return const <ParameterStubMethod>[];
 
     ParameterStubGenerator generator =
         new ParameterStubGenerator(_compiler, namer, backend);
     return generator.generateParameterStubs(element, canTearOff: canTearOff);
@@ skipping 112 matching lines @@
     bool canBeApplied = _methodCanBeApplied(element);
     bool canBeReflected = _methodCanBeReflected(element);
 
     bool needsTearOff = isApplyTarget &&
         (canBeReflected ||
             universe.staticFunctionsNeedingGetter.contains(element));
 
     String tearOffName =
         needsTearOff ? namer.getStaticClosureName(element) : null;
 
+
     String callName = null;
     if (needsTearOff) {
       Selector callSelector =
           new Selector.fromElement(element).toCallSelector();
       callName = namer.invocationName(callSelector);
     }
+    js.Expression functionType;
+    DartType type = element.type;
+    if (needsTearOff || canBeReflected) {
+      functionType = _generateFunctionType(type);
+    }
 
     int requiredParameterCount;
     var /* List | Map */ optionalParameterDefaultValues;
     if (canBeApplied || canBeReflected) {
       FunctionSignature signature = element.functionSignature;
       requiredParameterCount = signature.requiredParameterCount;
       optionalParameterDefaultValues =
           _computeParameterDefaultValues(signature);
     }
 
     // TODO(floitsch): we shouldn't update the registry in the middle of
     // building a static method.
     return new StaticDartMethod(element,
                                 name, _registry.registerHolder(holder), code,
                                 _generateParameterStubs(element, needsTearOff),
-                                callName, element.type,
+                                callName,
                                 needsTearOff: needsTearOff,
                                 tearOffName: tearOffName,
                                 canBeApplied: canBeApplied,
                                 canBeReflected: canBeReflected,
                                 requiredParameterCount: requiredParameterCount,
                                 optionalParameterDefaultValues:
-                                  optionalParameterDefaultValues);
+                                  optionalParameterDefaultValues,
+                                functionType: functionType);
   }
 
   void _registerConstants(OutputUnit outputUnit,
                           Iterable<ConstantValue> constantValues) {
     // `constantValues` is null if an outputUnit doesn't contain any constants.
     if (constantValues == null) return;
     for (ConstantValue constantValue in constantValues) {
       _registry.registerConstant(outputUnit, constantValue);
       assert(!_constants.containsKey(constantValue));
       String name = namer.constantName(constantValue);
       String constantObject = namer.globalObjectForConstant(constantValue);
       Holder holder = _registry.registerHolder(constantObject);
       Constant constant = new Constant(name, holder, constantValue);
       _constants[constantValue] = constant;
     }
   }
 }