Refactor the Heap into ThreadHeap to prepare for per thread heaps

third_party/WebKit/Source/platform/heap/PagePool.h

Index: third_party/WebKit/Source/platform/heap/PagePool.h
diff --git a/third_party/WebKit/Source/platform/heap/PagePool.h b/third_party/WebKit/Source/platform/heap/PagePool.h
index 34633ed4db49a51d3b6acd78c9fd154f6446a75b..5bf86a2f60286ce9e57c449fd59003b1b6f42906 100644
--- a/third_party/WebKit/Source/platform/heap/PagePool.h
+++ b/third_party/WebKit/Source/platform/heap/PagePool.h
@@ -20,7 +20,7 @@ class PagePool {
 protected:
     PagePool()
     {
-        for (int i = 0; i < BlinkGC::NumberOfHeaps; ++i)
+        for (int i = 0; i < BlinkGC::NumberOfArenas; ++i)
             m_pool[i] = nullptr;
     }
 
@@ -36,7 +36,7 @@ protected:
         PoolEntry* next;
     };
 
-    PoolEntry* m_pool[BlinkGC::NumberOfHeaps];
+    PoolEntry* m_pool[BlinkGC::NumberOfArenas];
 };
 
 // Once pages have been used for one type of thread heap they will never be
@@ -54,7 +54,7 @@ public:
     PageMemory* takeFreePage(int);
 
 private:
-    Mutex m_mutex[BlinkGC::NumberOfHeaps];
+    Mutex m_mutex[BlinkGC::NumberOfArenas];
 };
 
 class OrphanedPagePool : public PagePool<BasePage> {