Adds a CancellableTaskFactory and exposes postLoadingTasks to Blink

Source/core/html/parser/HTMLDocumentParser.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
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    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
@@ skipping 512 matching lines @@
     }
 
     // FIXME: Pass in current input length.
     TRACE_EVENT_BEGIN1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"), "ParseHTML", "beginData", InspectorParseHtmlEvent::beginData(document(), lineNumber().zeroBasedInt()));
     // FIXME(361045): remove InspectorInstrumentation calls once DevTools Timeline migrates to tracing.
     InspectorInstrumentationCookie cookie = InspectorInstrumentation::willWriteHTML(document(), lineNumber().zeroBasedInt());
 
     SpeculationsPumpSession session(m_pumpSpeculationsSessionNestingLevel, contextForParsingSession());
     while (!m_speculations.isEmpty()) {
         ASSERT(!isScheduledForResume());
+
+        if (m_parserScheduler->yieldIfNeeded(session, m_speculations.first()->startingScript))
+            break;
+
         size_t elementTokenCount = processParsedChunkFromBackgroundParser(m_speculations.takeFirst());
         session.addedElementTokens(elementTokenCount);
 
         // Always check isParsing first as m_document may be null.
         // Surprisingly, isScheduledForResume() may be set here as a result of
         // processParsedChunkFromBackgroundParser running arbitrary javascript
         // which invokes nested event loops. (e.g. inspector breakpoints)
         if (!isParsing() || isWaitingForScripts() || isScheduledForResume())
             break;
-
-        if (m_speculations.isEmpty() || m_parserScheduler->yieldIfNeeded(session, m_speculations.first()->startingScript))
-            break;
     }
 
     TRACE_EVENT_END1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"), "ParseHTML", "endLine", lineNumber().zeroBasedInt());
     // FIXME(361045): remove InspectorInstrumentation calls once DevTools Timeline migrates to tracing.
     InspectorInstrumentation::didWriteHTML(cookie, lineNumber().zeroBasedInt());
     TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"), "UpdateCounters", "data", InspectorUpdateCountersEvent::data());
 }
 
 void HTMLDocumentParser::forcePlaintextForTextDocument()
 {
@@ skipping 524 matching lines @@
 void HTMLDocumentParser::setDecoder(PassOwnPtr<TextResourceDecoder> decoder)
 {
     ASSERT(decoder);
     DecodedDataDocumentParser::setDecoder(decoder);
 
     if (m_haveBackgroundParser)
         HTMLParserThread::shared()->postTask(bind(&BackgroundHTMLParser::setDecoder, m_backgroundParser, takeDecoder()));
 }
 
 }