Revert of Revert "Revert of [oilpan]: Change marking to do precise roots first and conservative

Source/platform/heap/Heap.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 951 matching lines @@
 #if ENABLE(ASSERT)
     static bool weakTableRegistered(const void*);
 #endif
 
     template<typename T> static Address allocate(size_t);
     template<typename T> static Address reallocate(void* previous, size_t);
 
     static void collectGarbage(ThreadState::StackState);
     static void collectGarbageForTerminatingThread(ThreadState*);
     static void collectAllGarbage();
-    template<CallbackInvocationMode Mode> static void processMarkingStack();
-    static void globalWeakProcessingAndCleanup();
+    template<CallbackInvocationMode Mode> static void traceRootsAndPerformGlobalWeakProcessing();
     static void setForcePreciseGCForTesting();
 
     static void prepareForGC();
 
     // Conservatively checks whether an address is a pointer in any of the thread
     // heaps. If so marks the object pointed to as live.
     static Address checkAndMarkPointer(Visitor*, Address);
 
 #if ENABLE(GC_TRACING)
     // Dump the path to specified object on the next GC. This method is to be invoked from GDB.
@@ skipping 1392 matching lines @@
 };
 
 template<typename T>
 struct IfWeakMember<WeakMember<T> > {
     static bool isDead(Visitor* visitor, const WeakMember<T>& t) { return !visitor->isAlive(t.get()); }
 };
 
 }
 
 #endif // Heap_h