Refactoring WorkletThreadBackingHolder with template pattern

third_party/WebKit/Source/modules/webaudio/AudioWorkletThread.h

Index: third_party/WebKit/Source/modules/webaudio/AudioWorkletThread.h
diff --git a/third_party/WebKit/Source/modules/webaudio/AudioWorkletThread.h b/third_party/WebKit/Source/modules/webaudio/AudioWorkletThread.h
index df7683c46d04aee5d3cbd4949197d8a2943d2845..00e1f7b39baec698a7a35a48423f32f92f98c908 100644
--- a/third_party/WebKit/Source/modules/webaudio/AudioWorkletThread.h
+++ b/third_party/WebKit/Source/modules/webaudio/AudioWorkletThread.h
@@ -7,6 +7,7 @@
 
 #include "core/workers/WorkerLoaderProxy.h"
 #include "core/workers/WorkerThread.h"
+#include "core/workers/WorkletThreadHolder.h"
 #include "modules/ModulesExport.h"
 #include <memory>
 
@@ -36,10 +37,10 @@ class MODULES_EXPORT AudioWorkletThread final : public WorkerThread {
   static void collectAllGarbage();
 
   static void ensureSharedBackingThread();
-  static void createSharedBackingThreadForTest();
-
   static void clearSharedBackingThread();
 
+  static void createSharedBackingThreadForTest();
+
  protected:
   WorkerOrWorkletGlobalScope* createWorkerGlobalScope(
       std::unique_ptr<WorkerThreadStartupData>) final;