Support new getter syntax (no formal parameter list)

runtime/vm/object.h

Index: runtime/vm/object.h
===================================================================
--- runtime/vm/object.h	(revision 10540)
+++ runtime/vm/object.h	(working copy)
@@ -1533,6 +1533,16 @@
                     malformed_error);
   }
 
+  // Returns true if this function represents an explicit getter function.
+  bool IsGetterFunction() const {
+    return kind() == RawFunction::kGetterFunction;
+  }
+
+  // Returns true if this function represents an explicit setter function.
+  bool IsSetterFunction() const {
+    return kind() == RawFunction::kSetterFunction;
+  }
+
   // Returns true if this function represents a (possibly implicit) closure
   // function.
   bool IsClosureFunction() const {