[snapshot] revisit snapshot API.

include/v8.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /** \mainpage V8 API Reference Guide
  *
  * V8 is Google's open source JavaScript engine.
  *
  * This set of documents provides reference material generated from the
  * V8 header file, include/v8.h.
@@ skipping 4472 matching lines @@
  */
 class V8_EXPORT FunctionTemplate : public Template {
  public:
   /** Creates a function template.*/
   static Local<FunctionTemplate> New(
       Isolate* isolate, FunctionCallback callback = 0,
       Local<Value> data = Local<Value>(),
       Local<Signature> signature = Local<Signature>(), int length = 0);
 
   /** Get a template included in the snapshot by index. */
-  static Local<FunctionTemplate> FromSnapshot(Isolate* isolate, size_t index);
+  static MaybeLocal<FunctionTemplate> FromSnapshot(Isolate* isolate,
+                                                   size_t index);
 
   /**
    * Creates a function template with a fast handler. If a fast handler is set,
    * the callback cannot be null.
    */
   static Local<FunctionTemplate> NewWithFastHandler(
       Isolate* isolate, FunctionCallback callback,
       experimental::FastAccessorBuilder* fast_handler = nullptr,
       Local<Value> data = Local<Value>(),
       Local<Signature> signature = Local<Signature>(), int length = 0);
@@ skipping 157 matching lines @@
  */
 class V8_EXPORT ObjectTemplate : public Template {
  public:
   /** Creates an ObjectTemplate. */
   static Local<ObjectTemplate> New(
       Isolate* isolate,
       Local<FunctionTemplate> constructor = Local<FunctionTemplate>());
   static V8_DEPRECATED("Use isolate version", Local<ObjectTemplate> New());
 
   /** Get a template included in the snapshot by index. */
-  static Local<ObjectTemplate> FromSnapshot(Isolate* isolate, size_t index);
+  static MaybeLocal<ObjectTemplate> FromSnapshot(Isolate* isolate,
+                                                 size_t index);
 
   /** Creates a new instance of this template.*/
   V8_DEPRECATE_SOON("Use maybe version", Local<Object> NewInstance());
   V8_WARN_UNUSED_RESULT MaybeLocal<Object> NewInstance(Local<Context> context);
 
   /**
    * Sets an accessor on the object template.
    *
    * Whenever the property with the given name is accessed on objects
    * created from this ObjectTemplate the getter and setter callbacks
@@ skipping 2439 matching lines @@
    *
    * \param global_object An optional global object to be reused for
    * the newly created context. This global object must have been
    * created by a previous call to Context::New with the same global
    * template. The state of the global object will be completely reset
    * and only object identify will remain.
    */
   static Local<Context> New(
       Isolate* isolate, ExtensionConfiguration* extensions = NULL,
       Local<ObjectTemplate> global_template = Local<ObjectTemplate>(),
-      Local<Value> global_object = Local<Value>(),
-      size_t context_snapshot_index = 0);
+      Local<Value> global_object = Local<Value>());
+
+  static MaybeLocal<Context> FromSnapshot(
+      Isolate* isolate, size_t context_snapshot_index,
+      ExtensionConfiguration* extensions = NULL,
+      Local<ObjectTemplate> global_template = Local<ObjectTemplate>(),
+      Local<Value> global_object = Local<Value>());
 
   /**
    * Sets the security token for the context.  To access an object in
    * another context, the security tokens must match.
    */
   void SetSecurityToken(Local<Value> token);
 
   /** Restores the security token to the default value. */
   void UseDefaultSecurityToken();
 
@@ skipping 1735 matching lines @@
  */
 
 
 }  // namespace v8
 
 
 #undef TYPE_CHECK
 
 
 #endif  // INCLUDE_V8_H_