Release Oilpan heap singletons prior to LSan leak detection.

third_party/WebKit/Source/platform/WebThreadSupportingGC.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "platform/WebThreadSupportingGC.h"
 
 #include "platform/heap/SafePoint.h"
 #include "public/platform/WebScheduler.h"
 #include "wtf/Threading.h"
@@ skipping 36 matching lines @@
 }
 
 void WebThreadSupportingGC::initialize()
 {
     ThreadState::attach();
     m_gcTaskRunner = adoptPtr(new GCTaskRunner(m_thread));
 }
 
 void WebThreadSupportingGC::shutdown()
 {
+#if defined(LEAK_SANITIZER)
+    ThreadState::current()->releaseStaticPersistentNodes();
+#endif
     // Ensure no posted tasks will run from this point on.
     m_gcTaskRunner.clear();
 
     // Shutdown the thread (via its scheduler) only when the thread is created
     // and is owned by this instance.
     if (m_owningThread)
         m_owningThread->scheduler()->shutdown();
 
     ThreadState::detach();
 }
 
 } // namespace blink