Oilpan: Prepare moving AccessibilityText to the heap

Source/modules/accessibility/AXObject.h

Index: Source/modules/accessibility/AXObject.h
diff --git a/Source/modules/accessibility/AXObject.h b/Source/modules/accessibility/AXObject.h
index 3bb558598ab70e89b0b9decae739cf8cac1543f8..a02bc6331fdfb487c536a7a05d2cdd7f49627c13 100644
--- a/Source/modules/accessibility/AXObject.h
+++ b/Source/modules/accessibility/AXObject.h
@@ -214,21 +214,33 @@ enum AccessibilityState {
     AXVisitedState
 };
 
-struct AccessibilityText {
-    String text;
-    AccessibilityTextSource textSource;
-    RefPtr<AXObject> textElement;
-
-    AccessibilityText(const String& t, const AccessibilityTextSource& s)
-    : text(t)
-    , textSource(s)
-    { }
+class AccessibilityText final : public NoBaseWillBeGarbageCollectedFinalized<AccessibilityText> {
+public:
+    static PassOwnPtrWillBeRawPtr<AccessibilityText> create(const String& text, const AccessibilityTextSource& source)
+    {
+        return adoptPtrWillBeNoop(new AccessibilityText(text, source, nullptr));
+    }
+    static PassOwnPtrWillBeRawPtr<AccessibilityText> create(const String& text, const AccessibilityTextSource& source, const RefPtr<AXObject> element)
+    {
+        return adoptPtrWillBeNoop(new AccessibilityText(text, source, nullptr));
+    }
+
+    String text() const { return m_text; }
+    AccessibilityTextSource textSource() const { return m_textSource; }
+    AXObject* textElement() const { return m_textElement.get(); }
+
+    DEFINE_INLINE_TRACE() { }
 
-    AccessibilityText(const String& t, const AccessibilityTextSource& s, const RefPtr<AXObject> element)
-    : text(t)
-    , textSource(s)
-    , textElement(element)
+private:
+    AccessibilityText(const String& text, const AccessibilityTextSource& source, const PassRefPtr<AXObject> element)
+    : m_text(text)
+    , m_textSource(source)
+    , m_textElement(element)
     { }
+
+    String m_text;
+    AccessibilityTextSource m_textSource;
+    RefPtr<AXObject> m_textElement;
 };
 
 enum AccessibilityOrientation {