Oilpan: Remove OffHeapCollectionTrait

Source/modules/encryptedmedia/MediaKeySystemAccess.cpp

Index: Source/modules/encryptedmedia/MediaKeySystemAccess.cpp
diff --git a/Source/modules/encryptedmedia/MediaKeySystemAccess.cpp b/Source/modules/encryptedmedia/MediaKeySystemAccess.cpp
index e649b987ed4410d484e55d255b4f6117bd231ba5..53f5f954473bbeefbf3cfbd90184baa8d96847ab 100644
--- a/Source/modules/encryptedmedia/MediaKeySystemAccess.cpp
+++ b/Source/modules/encryptedmedia/MediaKeySystemAccess.cpp
@@ -73,9 +73,9 @@ static Vector<String> convertInitDataTypes(const WebVector<WebEncryptedMediaInit
     return result;
 }
 
-static Vector<MediaKeySystemMediaCapability> convertCapabilities(const WebVector<WebMediaKeySystemMediaCapability>& capabilities)
+static HeapVector<MediaKeySystemMediaCapability> convertCapabilities(const WebVector<WebMediaKeySystemMediaCapability>& capabilities)
 {
-    Vector<MediaKeySystemMediaCapability> result;
+    HeapVector<MediaKeySystemMediaCapability> result;
     result.reserveCapacity(capabilities.size());
     for (size_t i = 0; i < capabilities.size(); i++) {
         MediaKeySystemMediaCapability capability;