HRTFDatabaseLoader needs to acquire a lock when accessing m_hrtfDatabase

Source/platform/audio/HRTFDatabaseLoader.h

Index: Source/platform/audio/HRTFDatabaseLoader.h
diff --git a/Source/platform/audio/HRTFDatabaseLoader.h b/Source/platform/audio/HRTFDatabaseLoader.h
index 73dac33ba43636627fe6ceae96aeee30b534abda..27d001788ba2575f3819ccea81114146b29c312a 100644
--- a/Source/platform/audio/HRTFDatabaseLoader.h
+++ b/Source/platform/audio/HRTFDatabaseLoader.h
@@ -51,7 +51,7 @@ public:
     ~HRTFDatabaseLoader();
 
     // Returns true once the default database has been completely loaded.
-    bool isLoaded() const;
+    bool isLoaded();
 
     // waitForLoaderThreadCompletion() may be called more than once and is thread-safe.
     void waitForLoaderThreadCompletion();
@@ -73,10 +73,10 @@ private:
     // This must be called from the main thread.
     void loadAsynchronously();
 
+    // Holding a m_lock is required when accessing m_hrtfDatabase since we access it from multiple threads.
+    Mutex m_lock;
     OwnPtr<HRTFDatabase> m_hrtfDatabase;
 
-    // Holding a m_threadLock is required when accessing m_databaseLoaderThread since we access it from multiple threads.
-    Mutex m_threadLock;
     OwnPtr<WebThread> m_databaseLoaderThread;
 
     float m_databaseSampleRate;