Add Dart_Null, Dart_True, and Dart_False.

runtime/include/dart_api.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.
 
 #ifndef INCLUDE_DART_API_H_
 #define INCLUDE_DART_API_H_
 
 /** \mainpage Dart Embedding API Reference
  *
  * Dart is a class-based programming language for creating structured
@@ skipping 121 matching lines @@
 
 /**
  * Allocates a persistent handle for an object.
  *
  * This handle has the lifetime of the current isolate unless it is
  * explicitly deallocated by calling Dart_DeletePersistentHandle.
  *
  * Requires there to be a current isolate.
  */
 DART_EXPORT Dart_Handle Dart_NewPersistentHandle(Dart_Handle object);
-// TODO(turnidge): This function currently only works when passes a
-// local handle.  Make it work for both local and persistent handles.
 
 /**
  * Deallocates a persistent handle.
  *
  * Requires there to be a current isolate.
  */
 DART_EXPORT void Dart_DeletePersistentHandle(Dart_Handle object);
 
 /**
  * Takes a persistent handle and makes it weak.
@@ skipping 279 matching lines @@
  *
  * The previous scope (if any) becomes the current scope.
  *
  * Requires there to be a current isolate.
  */
 DART_EXPORT void Dart_ExitScope();
 
 // --- Objects ----
 
 /**
+ * Returns the null object.
+ *
+ * Requires there to be a current isolate.
+ *
+ * \return A handle to the null object.
+ */
+DART_EXPORT Dart_Handle Dart_Null();
+
+/**
  * Is this object null?
  */
 DART_EXPORT bool Dart_IsNull(Dart_Handle object);
 
 /**
  * Converts an object to a string.
  *
  * If an exception occurs during the conversion, this is treated as an
  * error.
  *
@@ skipping 107 matching lines @@
  *   the next call to Dart_ExitScope.
  *
  * \return A valid handle if no error occurs during the operation.
  */
 DART_EXPORT Dart_Handle Dart_IntegerValueHexCString(Dart_Handle integer,
                                                     const char** value);
 
 // --- Booleans ----
 
 /**
+ * Returns the True object.
+ *
+ * Requires there to be a current isolate.
+ *
+ * \return A handle to the True object.
+ */
+DART_EXPORT Dart_Handle Dart_True();
+
+/**
+ * Returns the False object.
+ *
+ * Requires there to be a current isolate.
+ *
+ * \return A handle to the False object.
+ */
+DART_EXPORT Dart_Handle Dart_False();
+
+/**
  * Is this object a Boolean?
  */
 DART_EXPORT bool Dart_IsBoolean(Dart_Handle object);
 
 /**
  * Returns a Boolean with the provided value.
  *
  * \param value true or false.
  *
  * \return The Boolean object if no errors occurs. Otherwise returns
@@ skipping 537 matching lines @@
 
 // --- Profiling support ----
 
 // External pprof support for gathering and dumping symbolic
 // information that can be used for better profile reports for
 // dynamically generated code.
 DART_EXPORT void Dart_InitPprofSupport();
 DART_EXPORT void Dart_GetPprofSymbolInfo(void** buffer, int* buffer_size);
 
 #endif  // INCLUDE_DART_API_H_