CustomElements: upgrade element patch

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/V8ErrorHandler.h"
 #include "bindings/core/v8/V8HiddenValue.h"
 #include "bindings/core/v8/V8ScriptRunner.h"
 #include "bindings/core/v8/V8ThrowException.h"
 #include "core/dom/ExceptionCode.h"
+#include "core/events/ErrorEvent.h"
 #include "core/html/HTMLElement.h"
 #include "core/html/HTMLUnknownElement.h"
 #include "v8.h"
 #include "wtf/Allocator.h"
 
 namespace blink {
 
 // Retrieves the custom elements constructor -> name map, creating it
 // if necessary. The same map is used to keep prototypes alive.
 static v8::Local<v8::Map> ensureCustomElementsRegistryMap(
@@ skipping 196 matching lines @@
         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);
 
     Element* result = runConstructor();
-    if (!result)
+    if (tryCatch.HasCaught())
         return false;
 
     if (result != element) {
+        const String& message = "custom element constructors must call super() first and must "

[haraken, 2016/07/26 11:25:16]

I want to create a helper method that runs line 238 - 255.
ScriptCustomElementDefinition::fireErrorEvent() or something.

+            "not return a different object";
         V8ThrowException::throwException(
             V8ThrowException::createDOMException(
                 m_scriptState->isolate(),
                 InvalidStateError,
-                "custom element constructors must call super() first and must "
-                "not return a different object",
+                message,
                 constructor()),
             m_scriptState->isolate());
+
+        v8::Local<v8::Function> function = constructor().As<v8::Function>();
+        ErrorEvent* event = ErrorEvent::create(
+            message,
+            SourceLocation::fromFunction(function),
+            &m_scriptState->world());
+        V8ErrorHandler::storeExceptionOnErrorEventWrapper(m_scriptState.get(), event, tryCatch.Exception(), m_scriptState->context()->Global());

[haraken, 2016/07/26 11:46:16]

BTW, is this line needed?

e.g., Lazy event listeners are not setting the exception on their error events.

https://cs.chromium.org/chromium/src/third_party/WebKit/Source/bindings/core/...

+        ExecutionContext* executionContext = m_scriptState->getExecutionContext();
+        executionContext->reportException(event, NotSharableCrossOrigin);

[haraken, 2016/07/22 09:31:53]

Do we really need to report the exception synchronously? This is the only place
we're doing that (outside error event handlers).

+
         return false;
     }
 
     return true;
 }
 
 Element* ScriptCustomElementDefinition::runConstructor()
 {
     v8::Isolate* isolate = m_scriptState->isolate();
     DCHECK(ScriptState::current(isolate) == m_scriptState);
@@ skipping 93 matching lines @@
         v8String(isolate, name.localName()),
         v8StringOrNull(isolate, oldValue),
         v8StringOrNull(isolate, newValue),
         v8String(isolate, name.namespaceURI()),
     };
     runCallback(m_attributeChangedCallback.newLocal(isolate), element,
         argc, argv);
 }
 
 } // namespace blink