Oilpan: Replace checkHeader() with ASSERT(checkHeader())

Source/platform/heap/Handle.h

 /*
  * Copyright (C) 2014 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 774 matching lines @@
         // TODO(haraken): What we really want to check here is that the pointer
         // is a traceable object. In other words, the pointer is either of:
         //
         //   (a) a pointer to the head of an on-heap object.
         //   (b) a pointer to the head of an on-heap mixin object.
         //
         // We can check it by calling Heap::isHeapObjectAlive(m_raw),
         // but we cannot call it here because it requres to include T.h.
         // So we currently implement only the check for (a).
         if (!IsGarbageCollectedMixin<T>::value)
-            HeapObjectHeader::fromPayload(m_raw)->checkHeader();
+            ASSERT(HeapObjectHeader::fromPayload(m_raw)->checkHeader());
 #endif
     }
 
     T* m_raw;
 
     template<bool x, WTF::WeakHandlingFlag y, WTF::ShouldWeakPointersBeMarkedStrongly z, typename U, typename V> friend struct CollectionBackingTraceTrait;
     friend class Visitor;
 
 };
 
@@ skipping 481 matching lines @@
 struct ParamStorageTraits<RawPtr<T>> : public PointerParamStorageTraits<T*, blink::IsGarbageCollectedType<T>::value> {
     static_assert(sizeof(T), "T must be fully defined");
 };
 
 template<typename T>
 PassRefPtr<T> adoptRef(blink::RefCountedGarbageCollected<T>*) = delete;
 
 } // namespace WTF
 
 #endif