Always enable Oilpan for EventSource.

Source/core/fileapi/FileReader.cpp

Index: Source/core/fileapi/FileReader.cpp
diff --git a/Source/core/fileapi/FileReader.cpp b/Source/core/fileapi/FileReader.cpp
index f5bf8690195edb7761fc53d15ebaa556dfce3e36..861e23ac7ca847e826a3a195bba9e5a84f03ab6b 100644
--- a/Source/core/fileapi/FileReader.cpp
+++ b/Source/core/fileapi/FileReader.cpp
@@ -319,7 +319,7 @@ void FileReader::executePendingRead()
     ASSERT(m_loadingState == LoadingStatePending);
     m_loadingState = LoadingStateLoading;
 
-    m_loader = adoptPtr(new FileReaderLoader(m_readType, this));
+    m_loader = FileReaderLoader::create(m_readType, this);
     m_loader->setEncoding(m_encoding);
     m_loader->setDataType(m_blobType);
     m_loader->start(executionContext(), m_blobDataHandle);