Split "Online" and "Offline" AudioContext processing

Source/modules/webaudio/PannerNode.cpp

Index: Source/modules/webaudio/PannerNode.cpp
diff --git a/Source/modules/webaudio/PannerNode.cpp b/Source/modules/webaudio/PannerNode.cpp
index 6504526cb60f67632f53553ec54cb4a2989f1bf8..66115a88d87dd0330769f20a336a730312ae7343 100644
--- a/Source/modules/webaudio/PannerNode.cpp
+++ b/Source/modules/webaudio/PannerNode.cpp
@@ -107,14 +107,15 @@ void PannerHandler::process(size_t framesToProcess)
     MutexTryLocker tryListenerLocker(listener()->listenerLock());
 
     if (tryLocker.locked() && tryListenerLocker.locked()) {
-        // HRTFDatabase should be loaded before proceeding for offline audio context when the panning model is HRTF.
+        // HRTFDatabase should be loaded before proceeding when the panning model is HRTF.
         if (m_panningModel == Panner::PanningModelHRTF && !listener()->isHRTFDatabaseLoaded()) {
-            if (context()->isOfflineContext()) {
-                listener()->waitForHRTFDatabaseLoaderThreadCompletion();
-            } else {
+            if (context()->hasRealtimeConstraint()) {
+                // Some AudioContexts cannot block on the HRTFDatabase loader.
                 destination->zero();
                 return;
             }
+
+            listener()->waitForHRTFDatabaseLoaderThreadCompletion();
         }
 
         // Apply the panning effect.