Add Dart_Allocate to the C++ API

runtime/include/dart_api.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 INCLUDE_DART_API_H_
 #define INCLUDE_DART_API_H_
 
 /** \mainpage Dart Embedding API Reference
@@ skipping 1735 matching lines @@
  * \return If the constructor is called and completes successfully,
  *   then the new object. If an error occurs during execution, then an
  *   error handle is returned.
  */
 DART_EXPORT Dart_Handle Dart_New(Dart_Handle clazz,
                                  Dart_Handle constructor_name,
                                  int number_of_arguments,
                                  Dart_Handle* arguments);
 
 /**
+ * Allocate a new object without invoking a constructor.
+ *
+ * \param type The type of an object to be allocated.
+ *
+ * \return The new object. If an error occurs during execution, then an
+ *   error handle is returned.
+ */
+DART_EXPORT Dart_Handle Dart_Allocate(Dart_Handle type);
+
+/**
  * Invokes a method or function.
  *
  * The 'target' parameter may be an object, class, or library.  If
  * 'target' is an object, then this function will invoke an instance
  * method.  If 'target' is a class, then this function will invoke a
  * static method.  If 'target' is a library, then this function will
  * invoke a top-level function from that library.
  *
  * This function ignores visibility (leading underscores in names).
  *
@@ skipping 408 matching lines @@
  *
  * \param object An object.
  * \param peer A value to store in the peer field.
  *
  * \return Returns an error if 'object' is a subtype of Null, num, or
  *   bool.
  */
 DART_EXPORT Dart_Handle Dart_SetPeer(Dart_Handle object, void* peer);
 
 #endif  /* INCLUDE_DART_API_H_ */  /* NOLINT */