Oilpan: Prepare moving AXObject to heap

Source/core/dom/AXObjectCache.cpp

Index: Source/core/dom/AXObjectCache.cpp
diff --git a/Source/core/dom/AXObjectCache.cpp b/Source/core/dom/AXObjectCache.cpp
index 340616585a1efceb73bd691051ee2524ed4b56dc..7ac9b122083262bdb647f227d583a12fcc8b1974 100644
--- a/Source/core/dom/AXObjectCache.cpp
+++ b/Source/core/dom/AXObjectCache.cpp
@@ -40,7 +40,7 @@ void AXObjectCache::init(AXObjectCacheCreateFunction function)
     m_createFunction = function;
 }
 
-AXObjectCache* AXObjectCache::create(Document& document)
+PassOwnPtrWillBeRawPtr<AXObjectCache> AXObjectCache::create(Document& document)
 {
     ASSERT(m_createFunction);
     return (m_createFunction)(document);
@@ -55,22 +55,35 @@ AXObjectCache::~AXObjectCache()
 }
 
 ScopedAXObjectCache::ScopedAXObjectCache(Document& document)
-    : m_document(document)
-    , m_cache(0)
+#if ENABLE(OILPAN)
+    : m_isOwned(false)
+#else
+    : m_ownedCache(nullptr)
+#endif
+    , m_cache(nullptr)
 {
     if (AXObjectCache* existingCache = document.axObjectCache()) {
         m_cache = existingCache;
-        m_isScoped = false;
     } else {
-        m_isScoped = true;
-        m_cache = AXObjectCache::create(m_document);
+#if ENABLE(OILPAN)
+        m_isOwned = true;
+        m_cache = AXObjectCache::create(document);
+#else
+        m_ownedCache = AXObjectCache::create(document);
+        m_cache = m_ownedCache.get();
+#endif
     }
 }
 
 ScopedAXObjectCache::~ScopedAXObjectCache()
 {
-    if (m_isScoped)
-        delete m_cache;
+#if ENABLE(OILPAN)
+    if (m_isOwned) {
+#else
+    if (m_ownedCache) {
+#endif
+        m_cache->dispose();
+    }
 }
 
 AXObjectCache* ScopedAXObjectCache::get()