Fix type test for callable objects (issue 7338).

runtime/vm/object.h

 // 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.
 
 #ifndef VM_OBJECT_H_
 #define VM_OBJECT_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 593 matching lines @@
 
   // Check if this class represents the 'dynamic' class.
   bool IsDynamicClass() const { return id() == kDynamicCid; }
 
   // Check if this class represents the 'void' class.
   bool IsVoidClass() const { return id() == kVoidCid; }
 
   // Check if this class represents the 'Object' class.
   bool IsObjectClass() const { return id() == kInstanceCid; }
 
+  // Check if this class represents the 'Function' class.
+  bool IsFunctionClass() const;
+
   // Check if this class represents the 'List' class.
   bool IsListClass() const;
 
   // Check if this class represents a signature class.
   bool IsSignatureClass() const {
     return signature_function() != Object::null();
   }
   static bool IsSignatureClass(RawClass* cls) {
     return cls->ptr()->signature_function_ != Object::null();
   }
@@ skipping 5533 matching lines @@
 
 
 RawObject* MegamorphicCache::GetTargetFunction(const Array& array,
                                                intptr_t index) {
   return array.At((index * kEntryLength) + kTargetFunctionIndex);
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_