Make number of available threads isolate-dependent and expose it to ResourceConstraints.

include/v8.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 3799 matching lines @@
    *
    * \param physical_memory The total amount of physical memory on the current
    *   device, in bytes.
    */
   void ConfigureDefaults(uint64_t physical_memory);
 
   int max_young_space_size() const { return max_young_space_size_; }
   void set_max_young_space_size(int value) { max_young_space_size_ = value; }
   int max_old_space_size() const { return max_old_space_size_; }
   void set_max_old_space_size(int value) { max_old_space_size_ = value; }
-  int max_executable_size() { return max_executable_size_; }
+  int max_executable_size() const { return max_executable_size_; }
   void set_max_executable_size(int value) { max_executable_size_ = value; }
   uint32_t* stack_limit() const { return stack_limit_; }
   // Sets an address beyond which the VM's stack may not grow.
   void set_stack_limit(uint32_t* value) { stack_limit_ = value; }
+  int max_available_threads() const { return max_available_threads_; }
+  // Set the number of threads available to V8, assuming at least 1.
+  void set_max_available_threads(int value) {
+    max_available_threads_ = value;
+  }
 
  private:
   int max_young_space_size_;
   int max_old_space_size_;
   int max_executable_size_;
   uint32_t* stack_limit_;
+  int max_available_threads_;
 };
 
 
 V8_DEPRECATED(
     "Use SetResourceConstraints(isolate, constraints) instead",
     bool V8_EXPORT SetResourceConstraints(ResourceConstraints* constraints));
 
 
 /**
  * Sets the given ResourceConstraints on the given Isolate.
@@ skipping 2698 matching lines @@
  */
 
 
 }  // namespace v8
 
 
 #undef TYPE_CHECK
 
 
 #endif  // V8_H_