Oilpan: Implement bitmap marking

Source/platform/heap/ThreadState.h

 /*
  * Copyright (C) 2013 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 862 matching lines @@
     // heap page. If so, find the start of that object and mark it
     // using the given Visitor. Otherwise do nothing. The pointer must
     // be within the same aligned blinkPageSize as the this-pointer.
     //
     // This is used during conservative stack scanning to
     // conservatively mark all objects that could be referenced from
     // the stack.
     virtual void checkAndMarkPointer(Visitor*, Address) = 0;
     virtual bool contains(Address) = 0;
 
+    virtual void markObject(Address) = 0;
+    virtual bool objectIsMarked(Address) = 0;
+    virtual void clearObjectMarkBitMap() = 0;
+
 #if ENABLE(GC_PROFILE_MARKING)
     virtual const GCInfo* findGCInfo(Address) = 0;
 #endif
 
     Address address() { return reinterpret_cast<Address>(this); }
     PageMemory* storage() const { return m_storage; }
     ThreadState* threadState() const { return m_threadState; }
     const GCInfo* gcInfo() { return m_gcInfo; }
     virtual bool isLargeObject() { return false; }
     virtual void markOrphaned();
@@ skipping 15 matching lines @@
     // whether the page is part of a terminting thread or
     // if the page is traced after being terminated (orphaned).
     uintptr_t m_terminating : 1;
     uintptr_t m_tracedAfterOrphaned : 1;
     uintptr_t m_promptlyFreedSize : 17; // == blinkPageSizeLog2
 };
 
 } // namespace blink
 
 #endif // ThreadState_h