Oilpan: Replace RefPtrs to Document in core/{accessibility,animation,fetch} with Oilpan transition …

Source/core/animation/AnimationPlayerTest.cpp

Index: Source/core/animation/AnimationPlayerTest.cpp
diff --git a/Source/core/animation/AnimationPlayerTest.cpp b/Source/core/animation/AnimationPlayerTest.cpp
index 65680be906866e6498dc3b247ace27c6ef78add2..37660e69b825abd5b90229633d49dce2fa0d0acd 100644
--- a/Source/core/animation/AnimationPlayerTest.cpp
+++ b/Source/core/animation/AnimationPlayerTest.cpp
@@ -82,7 +82,7 @@ protected:
         return player->update(TimingUpdateOnDemand);
     }
 
-    RefPtr<Document> document;
+    RefPtrWillBePersistent<Document> document;
     RefPtrWillBePersistent<AnimationTimeline> timeline;
     RefPtrWillBePersistent<AnimationPlayer> player;
     TrackExceptionState exceptionState;