Run Mutation Observer and Custom Element callbacks consistently at microtask checkpoint

Source/core/html/parser/HTMLScriptRunner.cpp

 /*
  * Copyright (C) 2010 Google, Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
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  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 #include "config.h"
 #include "core/html/parser/HTMLScriptRunner.h"
 
 #include "bindings/v8/ScriptSourceCode.h"
-#include "core/dom/CustomElementRegistry.h"
 #include "core/dom/Element.h"
 #include "core/dom/Event.h"
 #include "core/dom/IgnoreDestructiveWriteCountIncrementer.h"
-#include "core/dom/MutationObserver.h"
+#include "core/dom/Microtask.h"
 #include "core/dom/ScriptElement.h"
 #include "core/html/parser/HTMLInputStream.h"
 #include "core/html/parser/HTMLScriptRunnerHost.h"
 #include "core/html/parser/NestingLevelIncrementer.h"
 #include "core/loader/cache/CachedScript.h"
 #include "core/page/Frame.h"
 #include "core/platform/NotImplemented.h"
 
 namespace WebCore {
 
@@ skipping 74 matching lines @@
 
 void HTMLScriptRunner::executePendingScriptAndDispatchEvent(PendingScript& pendingScript)
 {
     bool errorOccurred = false;
     ScriptSourceCode sourceCode = sourceFromPendingScript(pendingScript, errorOccurred);
 
     // Stop watching loads before executeScript to prevent recursion if the script reloads itself.
     if (pendingScript.cachedScript() && pendingScript.watchingForLoad())
         stopWatchingForLoad(pendingScript);
 
-    if (!isExecutingScript()) {
-        CustomElementRegistry::deliverAllLifecycleCallbacks();
-        MutationObserver::deliverAllMutations();
-    }
+    if (!isExecutingScript())
+        Microtask::performCheckpoint();
 
     // Clear the pending script before possible rentrancy from executeScript()
     RefPtr<Element> element = pendingScript.releaseElementAndClear();
     if (ScriptElement* scriptElement = toScriptElementIfPossible(element.get())) {
         NestingLevelIncrementer nestingLevelIncrementer(m_scriptNestingLevel);
         IgnoreDestructiveWriteCountIncrementer ignoreDestructiveWriteCountIncrementer(m_document);
         if (errorOccurred)
             scriptElement->dispatchErrorEvent();
         else {
             ASSERT(isExecutingScript());
@@ skipping 142 matching lines @@
         // time to time. The assertion is left in to help find those cases and
         // is being tracked by <https://bugs.webkit.org/show_bug.cgi?id=60559>.
         ASSERT(scriptElement);
         if (!scriptElement)
             return;
 
         // FIXME: This may be too agressive as we always deliver mutations at
         // every script element, even if it's not ready to execute yet. There's
         // unfortuantely no obvious way to tell if prepareScript is going to
         // execute the script from out here.
-        if (!isExecutingScript()) {
-            CustomElementRegistry::deliverAllLifecycleCallbacks();
-            MutationObserver::deliverAllMutations();
-        }
+        if (!isExecutingScript())
+            Microtask::performCheckpoint();
 
         InsertionPointRecord insertionPointRecord(m_host->inputStream());
         NestingLevelIncrementer nestingLevelIncrementer(m_scriptNestingLevel);
 
         scriptElement->prepareScript(scriptStartPosition);
 
         if (!scriptElement->willBeParserExecuted())
             return;
 
         if (scriptElement->willExecuteWhenDocumentFinishedParsing())
             requestDeferredScript(script);
         else if (scriptElement->readyToBeParserExecuted()) {
             if (m_scriptNestingLevel == 1) {
                 m_parserBlockingScript.setElement(script);
                 m_parserBlockingScript.setStartingPosition(scriptStartPosition);
             } else {
                 ScriptSourceCode sourceCode(script->textContent(), documentURLForScriptExecution(m_document), scriptStartPosition);
                 scriptElement->executeScript(sourceCode);
             }
         } else
             requestParsingBlockingScript(script);
     }
 }
 
 }