Use the scheduling mechanism provided by the platform

Source/core/html/parser/HTMLDocumentParser.cpp

Index: Source/core/html/parser/HTMLDocumentParser.cpp
diff --git a/Source/core/html/parser/HTMLDocumentParser.cpp b/Source/core/html/parser/HTMLDocumentParser.cpp
index 0ef764d72dfd6938a2a8037a8ac49af17154a3ca..ceff03996408e09d1e579ae1f5d9517b86101c63 100644
--- a/Source/core/html/parser/HTMLDocumentParser.cpp
+++ b/Source/core/html/parser/HTMLDocumentParser.cpp
@@ -44,6 +44,8 @@
 #include "platform/SharedBuffer.h"
 #include "platform/TraceEvent.h"
 #include "platform/scheduler/Scheduler.h"
+#include "public/platform/Platform.h"
+#include "public/platform/WebScheduler.h"
 #include "public/platform/WebThreadedDataReceiver.h"
 #include "wtf/Functional.h"
 
@@ -516,7 +518,7 @@ void HTMLDocumentParser::pumpPendingSpeculations()
         if (isStopped() || isWaitingForScripts())
             break;
 
-        if ((Scheduler::shared()->shouldYieldForHighPriorityWork() || currentTime() - startTime > parserTimeLimit) && !m_speculations.isEmpty()) {
+        if (((Platform::current()->scheduler() && Platform::current()->scheduler()->shouldYieldForHighPriorityWork()) || currentTime() - startTime > parserTimeLimit) && !m_speculations.isEmpty()) {
             m_parserScheduler->scheduleForResume();
             break;
         }