[api] Support sharing prototypes between FunctionTemplates

include/v8.h

Index: include/v8.h
diff --git a/include/v8.h b/include/v8.h
index ccac0244da949d0f762b0411c4c24e5f60f5c8a8..83bb67a9b1d8dfc88a10aac1998816eec0f00826 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -5134,7 +5134,11 @@ class V8_EXPORT FunctionTemplate : public Template {
   /** Get the InstanceTemplate. */
   Local<ObjectTemplate> InstanceTemplate();
 
-  /** Causes the function template to inherit from a parent function template.*/
+  /**
+   * Causes the function template to inherit from a parent function template.
+   * This means the the function's prototype.__proto__ is set to the parent
+   * function's prototype.
+   **/
   void Inherit(Local<FunctionTemplate> parent);
 
   /**
@@ -5144,6 +5148,14 @@ class V8_EXPORT FunctionTemplate : public Template {
   Local<ObjectTemplate> PrototypeTemplate();
 
   /**
+   * A PrototypeProviderTemplate is another function template whose prototype
+   * property is used for this template. This is mutually exclusive with setting
+   * a prototype template indirectly by calling PrototypeTemplate() or using
+   * Inherit().
+   **/
+  void SetPrototypeProviderTemplate(Local<FunctionTemplate> prototype_provider);
+
+  /**
    * Set the class name of the FunctionTemplate.  This is used for
    * printing objects created with the function created from the
    * FunctionTemplate as its constructor.