[WIP] Custom element upgrades

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/V8CustomElementsRegistry.h"
+#include "bindings/core/v8/V8Element.h"
 #include "bindings/core/v8/V8HiddenValue.h"
+#include "bindings/core/v8/V8ScriptRunner.h"
+#include "v8.h"
 #include "wtf/Allocator.h"
 
 namespace blink {
 
 // Custom elements stores state off the registry's wrapper. To avoid leaking
 // contexts, that state should be manipulated in the registry's wrapper
 // context. This helper retrieves the wrapper and enters its context.
 //
 // For example if there are two same-origin frames and script in frame
 // A does frameB.contentWindow.customElements.define the map should be
@@ skipping 125 matching lines @@
 
     return definition;
 }
 
 ScriptCustomElementDefinition::ScriptCustomElementDefinition(
     ScriptState* scriptState,
     const CustomElementDescriptor& descriptor,
     const v8::Local<v8::Object>& constructor,
     const v8::Local<v8::Object>& prototype)
     : CustomElementDefinition(descriptor)
+    , m_scriptState(scriptState)
     , m_constructor(scriptState->isolate(), constructor)
     , m_prototype(scriptState->isolate(), prototype)
 {
     // These objects are kept alive by references from the
     // CustomElementsRegistry wrapper set up by
     // ScriptCustomElementDefinition::create.
     m_constructor.setPhantom();
     m_prototype.setPhantom();
 }
 
+// https://html.spec.whatwg.org/multipage/scripting.html#upgrades
+bool ScriptCustomElementDefinition::upgrade(Element* element)
+{
+    if (!m_scriptState->contextIsValid())
+        return false;
+    ScriptState::Scope scope(m_scriptState.get());
+    v8::Isolate* isolate = m_scriptState->isolate();
+
+    // Step 5 says to rethrow the exception; but there is no one to
+    // catch it. The side effect is to report the error.
+    v8::TryCatch tryCatch(isolate);
+    tryCatch.SetVerbose(true);
+
+    ExecutionContext* executionContext = m_scriptState->getExecutionContext();
+    v8::Local<v8::Object> ctor = constructor(m_scriptState.get());
+    v8::Local<v8::Value> result;
+    if (!v8Call(V8ScriptRunner::callAsConstructor(
+        isolate,
+        ctor,
+        executionContext,
+        0,
+        nullptr),
+        result))
+        return false;
+
+    if (V8Element::toImplWithTypeCheck(isolate, result) != element) {
+        // TODO(dominicc): Throw InvalidStateError. Maybe Upgrade should
+        // take ExceptionState&?
+        return false;
+    }
+
+    return true;
+}
+
 v8::Local<v8::Object> ScriptCustomElementDefinition::constructor(
     ScriptState* scriptState) const
 {
     DCHECK(!m_constructor.isEmpty());
     return m_constructor.newLocal(scriptState->isolate());
 }
 
 v8::Local<v8::Object> ScriptCustomElementDefinition::prototype(
     ScriptState* scriptState) const
 {
     DCHECK(!m_prototype.isEmpty());
     return m_prototype.newLocal(scriptState->isolate());
 }
 
 } // namespace blink