Introduce WebTaskRunner Patch 3/5

Source/modules/webaudio/AbstractAudioContext.cpp

Index: Source/modules/webaudio/AbstractAudioContext.cpp
diff --git a/Source/modules/webaudio/AbstractAudioContext.cpp b/Source/modules/webaudio/AbstractAudioContext.cpp
index 4d1829550c665b389f5b602e819d38b79c843d26..d72c8451d78e50d3896c6c42ef87400c88dd6fde 100644
--- a/Source/modules/webaudio/AbstractAudioContext.cpp
+++ b/Source/modules/webaudio/AbstractAudioContext.cpp
@@ -770,7 +770,7 @@ void AbstractAudioContext::resolvePromisesForResume()
     // promises in the main thread.
     if (!m_isResolvingResumePromises && m_resumeResolvers.size() > 0) {
         m_isResolvingResumePromises = true;
-        Platform::current()->mainThread()->postTask(FROM_HERE, threadSafeBind(&AbstractAudioContext::resolvePromisesForResumeOnMainThread, this));
+        Platform::current()->mainThread()->taskRunner()->postTask(FROM_HERE, threadSafeBind(&AbstractAudioContext::resolvePromisesForResumeOnMainThread, this));
     }
 }