Get rid of fastMallocGoodSize() and replace it with something generic.

Source/wtf/WTF.cpp

Index: Source/wtf/WTF.cpp
diff --git a/Source/wtf/WTF.cpp b/Source/wtf/WTF.cpp
index bddb3c0902f685c6f19360fe3748933df7e59b69..479bc5305c6c6d39076988b3a89a4467a462636e 100644
--- a/Source/wtf/WTF.cpp
+++ b/Source/wtf/WTF.cpp
@@ -32,6 +32,7 @@
 #include "WTF.h"
 
 #include "wtf/PartitionAlloc.h"
+#include "wtf/QuantizedAllocation.h"
 
 #ifndef NDEBUG
 #include "wtf/MainThread.h"
@@ -41,8 +42,11 @@ namespace WTF {
 
 extern void initializeThreading();
 
+PartitionAllocator<4096> Partitions::m_bufferAllocator;
+
 void initialize(TimeFunction currentTimeFunction, TimeFunction monotonicallyIncreasingTimeFunction)
 {
+    QuantizedAllocation::init();
     Partitions::initialize();
     setCurrentTimeFunction(currentTimeFunction);
     setMonotonicallyIncreasingTimeFunction(monotonicallyIncreasingTimeFunction);
@@ -64,6 +68,4 @@ void Partitions::shutdown()
     m_bufferAllocator.shutdown();
 }
 
-PartitionAllocator<4096> Partitions::m_bufferAllocator;
-
 } // namespace WTF