Oilpan: Change Persistent<> data members to Member<> in HitTestResult.

Source/core/rendering/HitTestResult.cpp

Index: Source/core/rendering/HitTestResult.cpp
diff --git a/Source/core/rendering/HitTestResult.cpp b/Source/core/rendering/HitTestResult.cpp
index 129a1d2f47c4d3c37ff17c4c352f2ba6e4b2c1ba..8adfdb5409e5ae43551ad227af2eec6d83991285 100644
--- a/Source/core/rendering/HitTestResult.cpp
+++ b/Source/core/rendering/HitTestResult.cpp
@@ -113,6 +113,17 @@ HitTestResult& HitTestResult::operator=(const HitTestResult& other)
     return *this;
 }
 
+void HitTestResult::trace(Visitor* visitor)
+{
+    visitor->trace(m_innerNode);
+    visitor->trace(m_innerPossiblyPseudoNode);
+    visitor->trace(m_innerNonSharedNode);
+    visitor->trace(m_innerURLElement);
+#if ENABLE(OILPAN)
+    visitor->trace(m_rectBasedTestResult);
+#endif
+}
+
 PositionWithAffinity HitTestResult::position() const
 {
     if (!m_innerPossiblyPseudoNode)