Move FontResourceClient to Oilpan heap

third_party/WebKit/Source/core/fetch/ResourceOwner.h

Index: third_party/WebKit/Source/core/fetch/ResourceOwner.h
diff --git a/third_party/WebKit/Source/core/fetch/ResourceOwner.h b/third_party/WebKit/Source/core/fetch/ResourceOwner.h
index b2a45d081905ca96a2849550387d545276b2135f..7afc520c6a001e10d534a092f802929d8e4906e4 100644
--- a/third_party/WebKit/Source/core/fetch/ResourceOwner.h
+++ b/third_party/WebKit/Source/core/fetch/ResourceOwner.h
@@ -32,22 +32,49 @@
 #define ResourceOwner_h
 
 #include "core/fetch/Resource.h"
+#include <type_traits>
 
 namespace blink {
 
+template <typename R, typename C, bool isClientGarbageCollectedMixin>

[hiroshige, 2016/05/27 08:18:38]

|R| is not necessary?

nit optional: How about renaming |C| to |Client|, to make it consistent with
|isClientGarbageCollectedMixin|?

[yhirano, 2016/05/27 16:37:28]

Done.

+class ResourceOwnerBase;
+
+template <typename R, typename C>
+class ResourceOwnerBase<R, C, true> : public C {
+public:
+    DEFINE_INLINE_VIRTUAL_TRACE()
+    {
+        C::trace(visitor);
+    }
+};
+
+// TODO(yhirano): Remove this template once all ResourceClients become
+// GarbageCollectedMixin.
+template <typename R, typename C>
+class ResourceOwnerBase<R, C, false> : public GarbageCollectedMixin, public C {
+public:
+    DEFINE_INLINE_VIRTUAL_TRACE() {}
+};
+
 template<class R, class C = typename R::ClientType>
-class ResourceOwner : public GarbageCollectedMixin, public C {
+class ResourceOwner : public ResourceOwnerBase<R, C, std::is_base_of<GarbageCollectedMixin, C>::value> {
     USING_PRE_FINALIZER(ResourceOwner, clearResource);
 public:
     using ResourceType = R;
+    ~ResourceOwner() override {}
+    ResourceType* resource() const { return m_resource; }
 
-    virtual ~ResourceOwner();
-    ResourceType* resource() const { return m_resource.get(); }
-
-    DEFINE_INLINE_VIRTUAL_TRACE() { visitor->trace(m_resource); }
+    DEFINE_INLINE_TRACE()
+    {
+        visitor->trace(m_resource);
+        ResourceOwnerBase<R, C, std::is_base_of<GarbageCollectedMixin, C>::value>::trace(visitor);
+    }
 
 protected:
-    ResourceOwner();
+    ResourceOwner()
+    {
+        ThreadState::current()->registerPreFinalizer(this);
+    }
 
     void setResource(ResourceType*);
     void clearResource() { setResource(nullptr); }
@@ -57,17 +84,6 @@ private:
 };
 
 template<class R, class C>
-inline ResourceOwner<R, C>::ResourceOwner()
-{
-    ThreadState::current()->registerPreFinalizer(this);
-}
-
-template<class R, class C>
-inline ResourceOwner<R, C>::~ResourceOwner()
-{
-}
-
-template<class R, class C>
 inline void ResourceOwner<R, C>::setResource(R* newResource)
 {
     if (newResource == m_resource)