Implement spawnFunction from the new isolate api.

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 2901 matching lines @@
                                 Heap::Space space = Heap::kNew);
 
   static RawString* NewSymbol(const char* str);
   template<typename T>
   static RawString* NewSymbol(const T* characters, intptr_t len);
   static RawString* NewSymbol(const String& str);
   static RawString* NewSymbol(const String& str,
                               intptr_t begin_index,
                               intptr_t length);
 
+  static RawString* NewFormatted(const char* format, ...);
+
  protected:
   bool HasHash() const {
     ASSERT(Smi::New(0) == NULL);
     return (raw_ptr()->hash_ != NULL);
   }
 
   void SetLength(intptr_t value) const {
     // This is only safe because we create a new Smi, which does not cause
     // heap allocation.
     raw_ptr()->length_ = Smi::New(value);
@@ skipping 992 matching lines @@
 }
 
 
 void Context::SetAt(intptr_t index, const Instance& value) const {
   StorePointer(InstanceAddr(index), value.raw());
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_