[Bindings] Move and remove some private symbols from V8HiddenValue

third_party/WebKit/Source/bindings/core/v8/ScriptCustomElementDefinition.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "bindings/core/v8/ScriptCustomElementDefinition.h"
 
 #include "bindings/core/v8/ScriptState.h"
 #include "bindings/core/v8/V8Binding.h"
 #include "bindings/core/v8/V8BindingMacros.h"
 #include "bindings/core/v8/V8CustomElementRegistry.h"
 #include "bindings/core/v8/V8Element.h"
 #include "bindings/core/v8/V8ErrorHandler.h"
-#include "bindings/core/v8/V8HiddenValue.h"
 #include "bindings/core/v8/V8PrivateProperty.h"
 #include "bindings/core/v8/V8ScriptRunner.h"
 #include "bindings/core/v8/V8ThrowException.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/dom/custom/CustomElement.h"
 #include "core/events/ErrorEvent.h"
 #include "core/html/HTMLElement.h"
 #include "core/html/imports/HTMLImportsController.h"
 #include "v8.h"
 #include "wtf/Allocator.h"
 
 namespace blink {
 
 // Retrieves the custom elements constructor -> name map, creating it
 // if necessary.
 static v8::Local<v8::Map> ensureCustomElementRegistryMap(
     ScriptState* scriptState,
     CustomElementRegistry* registry) {
   CHECK(scriptState->world().isMainWorld());
-  v8::Local<v8::String> name =
-      V8HiddenValue::customElementsRegistryMap(scriptState->isolate());
+  v8::Isolate* isolate = scriptState->isolate();
+
+  V8PrivateProperty::Symbol symbol =
+      V8PrivateProperty::getCustomElementRegistryMap(isolate);
   v8::Local<v8::Object> wrapper = ToV8(registry, scriptState).As<v8::Object>();
-  v8::Local<v8::Value> map =
-      V8HiddenValue::getHiddenValue(scriptState, wrapper, name);
-  if (map.IsEmpty()) {
-    map = v8::Map::New(scriptState->isolate());
-    V8HiddenValue::setHiddenValue(scriptState, wrapper, name, map);
+  v8::Local<v8::Value> map = symbol.getOrUndefined(wrapper);
+  if (map->IsUndefined()) {

[haraken, 2017/03/30 14:04:45]

As I commented in the other CL, I'd prefer removing getOrUndefined and unify to
getOrEmpty().

[peria, 2017/04/04 05:48:58]

Acknowledged.

+    map = v8::Map::New(isolate);
+    symbol.set(wrapper, map);
   }
   return map.As<v8::Map>();
 }
 
 ScriptCustomElementDefinition* ScriptCustomElementDefinition::forConstructor(
     ScriptState* scriptState,
     CustomElementRegistry* registry,
     const v8::Local<v8::Value>& constructor) {
   v8::Local<v8::Map> map =
       ensureCustomElementRegistryMap(scriptState, registry);
   v8::Local<v8::Value> nameValue =
       map->Get(scriptState->context(), constructor).ToLocalChecked();
   if (!nameValue->IsString())
     return nullptr;
   AtomicString name = toCoreAtomicString(nameValue.As<v8::String>());
 
   // This downcast is safe because only
   // ScriptCustomElementDefinitions have a name associated with a V8
   // constructor in the map; see
   // ScriptCustomElementDefinition::create. This relies on three
   // things:
   //
   // 1. Only ScriptCustomElementDefinition adds entries to the map.
-  //    Audit the use of V8HiddenValue/hidden values in general and
-  //    how the map is handled--it should never be leaked to script.
+  //    Audit the use of private properties in general and how the
+  //    map is handled--it should never be leaked to script.
   //
   // 2. CustomElementRegistry does not overwrite definitions with a
   //    given name--see the CHECK in CustomElementRegistry::define
   //    --and adds ScriptCustomElementDefinitions to the map without
   //    fail.
   //
   // 3. The relationship between the CustomElementRegistry and its
   //    map is never mixed up; this is guaranteed by the bindings
   //    system which provides a stable wrapper, and the map hangs
   //    off the wrapper.
@@ skipping 287 matching lines @@
   v8::Local<v8::Value> argv[] = {
       v8String(isolate, name.localName()), v8StringOrNull(isolate, oldValue),
       v8StringOrNull(isolate, newValue),
       v8StringOrNull(isolate, name.namespaceURI()),
   };
   runCallback(m_attributeChangedCallback.newLocal(isolate), element,
               WTF_ARRAY_LENGTH(argv), argv);
 }
 
 }  // namespace blink