Replace string comparing to enum comparing.

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 0bef552ba1b4be0158dedf52151673f46e96eae1..fb19694993ec7ac8e67c70645c194eb621449042 100644
--- a/Source/modules/webaudio/PannerNode.cpp
+++ b/Source/modules/webaudio/PannerNode.cpp
@@ -127,8 +127,8 @@ void PannerNode::process(size_t framesToProcess)
     // The audio thread can't block on this lock, so we call tryLock() instead.
     MutexTryLocker tryLocker(m_processLock);
     if (tryLocker.locked()) {
-        // HRTFDatabase should be loaded before proceeding for offline audio context when panningModel() is "HRTF".
-        if (panningModel() == "HRTF" && !m_hrtfDatabaseLoader->isLoaded()) {
+        // HRTFDatabase should be loaded before proceeding for offline audio context when m_panningModel is HRTF.

[Raymond Toy, 2014/04/09 17:50:51]

Nit: Change "m_panningModel is HRTF" to just "the panning model is HRTF"

+        if (m_panningModel == HRTF && !m_hrtfDatabaseLoader->isLoaded()) {
             if (context()->isOfflineContext()) {
                 m_hrtfDatabaseLoader->waitForLoaderThreadCompletion();
             } else {