Restructure instance calls in optimizing compiler.

vm/ic_data.h

 // Copyright (c) 2011, 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.
 // Class for handling inline cache stubs
 
 // The caller of an instance function passes the IC-data array in a specific
 // register (ECX on ia32).
 // That array contains information relevant for the call site: function name and
 // inline cache data. Class ICData is a wrapper around that array.
 // The array format is:
@@ skipping 39 matching lines @@
   intptr_t NumberOfChecks() const;
 
   // Also updates the instance call at 'return_address_'.
   void AddCheck(const GrowableArray<const Class*>& classes,
                 const Function& target);
 
   void SetCheckAt(intptr_t index,
                   const GrowableArray<const Class*>& classes,
                   const Function& target);
 
+  void GetOneClassCheckAt(intptr_t index, Class* cls, Function* target) const;
+
   void GetCheckAt(intptr_t index,
                   GrowableArray<const Class*>* classes,
                   Function* target) const;
 
   static const int kNameIndex = 0;
   static const int kNumArgsCheckedIndex = 1;
   static const int kChecksStartIndex = 2;
 
  private:
   intptr_t ArrayElementsPerCheck() const;
 
   const Array* data_;
 
 
   DISALLOW_COPY_AND_ASSIGN(ICData);
 };
 
 }  // namespace dart
 
 #endif  // VM_IC_DATA_H_