Revert https://android-git.corp.google.com/g/#change,31178
as http://b/issue?id=2183371 is finally fixed.
diff --git a/JavaScriptCore/wtf/Threading.h b/JavaScriptCore/wtf/Threading.h
index 00d34f2..c5e8f2f 100644
--- a/JavaScriptCore/wtf/Threading.h
+++ b/JavaScriptCore/wtf/Threading.h
@@ -259,15 +259,8 @@
 #if USE(LOCKFREE_THREADSAFESHARED)
         atomicIncrement(&m_refCount);
 #else
-#if defined ANDROID // avoid constructing a class to avoid two mystery crashes
-        m_mutex.lock();
-#else
         MutexLocker locker(m_mutex);
-#endif
         ++m_refCount;
-#if defined ANDROID
-        m_mutex.unlock();
-#endif
 #endif
     }
 
@@ -294,16 +287,9 @@
 #else
         int refCount;
         {
-#if defined ANDROID // avoid constructing a class to avoid two mystery crashes
-            m_mutex.lock();
-#else
             MutexLocker locker(m_mutex);
-#endif
             --m_refCount;
             refCount = m_refCount;
-#if defined ANDROID
-            m_mutex.unlock();
-#endif
         }
         if (refCount <= 0)
             return true;