Enable Oilpan by default for webaudio/

Source/modules/webaudio/PeriodicWave.h

Index: Source/modules/webaudio/PeriodicWave.h
diff --git a/Source/modules/webaudio/PeriodicWave.h b/Source/modules/webaudio/PeriodicWave.h
index cff3daa836c8743085ce8e06dc99f00f0202d4cb..02bb52cbb879d0dcfd37c60e2b6f425f119cdd54 100644
--- a/Source/modules/webaudio/PeriodicWave.h
+++ b/Source/modules/webaudio/PeriodicWave.h
@@ -33,20 +33,19 @@
 #include "platform/audio/AudioArray.h"
 #include "wtf/Float32Array.h"
 #include "wtf/Forward.h"
-#include "wtf/RefCounted.h"
 #include "wtf/Vector.h"
 
 namespace blink {
 
-class PeriodicWave : public RefCountedWillBeGarbageCollectedFinalized<PeriodicWave>, public ScriptWrappable {
+class PeriodicWave : public GarbageCollectedFinalized<PeriodicWave>, public ScriptWrappable {
 public:
-    static PassRefPtrWillBeRawPtr<PeriodicWave> createSine(float sampleRate);
-    static PassRefPtrWillBeRawPtr<PeriodicWave> createSquare(float sampleRate);
-    static PassRefPtrWillBeRawPtr<PeriodicWave> createSawtooth(float sampleRate);
-    static PassRefPtrWillBeRawPtr<PeriodicWave> createTriangle(float sampleRate);
+    static PeriodicWave* createSine(float sampleRate);
+    static PeriodicWave* createSquare(float sampleRate);
+    static PeriodicWave* createSawtooth(float sampleRate);
+    static PeriodicWave* createTriangle(float sampleRate);
 
     // Creates an arbitrary periodic wave given the frequency components (Fourier coefficients).
-    static PassRefPtrWillBeRawPtr<PeriodicWave> create(float sampleRate, Float32Array* real, Float32Array* imag);
+    static PeriodicWave* create(float sampleRate, Float32Array* real, Float32Array* imag);
 
     // Returns pointers to the lower and higher wave data for the pitch range containing
     // the given fundamental frequency. These two tables are in adjacent "pitch" ranges