Support runtime check of function types.

sdk/lib/_internal/compiler/implementation/compiler.dart

Index: sdk/lib/_internal/compiler/implementation/compiler.dart
diff --git a/sdk/lib/_internal/compiler/implementation/compiler.dart b/sdk/lib/_internal/compiler/implementation/compiler.dart
index 177eefe4421865b1606816a6171c4e9f15d04481..96490f5c03790dbf7f869857c9fc4a0d3e50e52b 100644
--- a/sdk/lib/_internal/compiler/implementation/compiler.dart
+++ b/sdk/lib/_internal/compiler/implementation/compiler.dart
@@ -126,7 +126,8 @@ abstract class Backend {
     return new ItemCompilationContext();
   }
 
-  bool needsRti(ClassElement cls);
+  bool classNeedsRti(ClassElement cls);
+  bool methodNeedsRti(FunctionElement function);
 
   // The following methods are hooks for the backend to register its
   // helper methods.
@@ -152,7 +153,24 @@ abstract class Backend {
   void registerFallThroughError(TreeElements elements) {}
   void registerSuperNoSuchMethod(TreeElements elements) {}
   void registerConstantMap(TreeElements elements) {}
-  void registerRuntimeType(TreeElements elements) {}
+  /**
+   * Call this to register that an instantiated generic class has a call
+   * method.
+   */
+  void registerGenericCallMethod(Element callMethod,
+                                 Enqueuer enqueuer,
+                                 TreeElements elements) {}
+  /**
+   * Call this to register that a getter exists for a function on an
+   * instantiated generic class.
+   */
+  void registerGenericClosure(Element closure,
+                              Enqueuer enqueuer,
+                              TreeElements elements) {}
+  /**
+   * Call this to register that the [:runtimeType:] property has been accessed.
+   */
+  void registerRuntimeType(Enqueuer enqueuer, TreeElements elements) {}
 
   void registerRequiredType(DartType type, Element enclosingElement) {}
   void registerClassUsingVariableExpression(ClassElement cls) {}