Refactor the Heap into ThreadHeap to prepare for per thread heaps

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

Index: third_party/WebKit/Source/platform/heap/HeapPage.h
diff --git a/third_party/WebKit/Source/platform/heap/HeapPage.h b/third_party/WebKit/Source/platform/heap/HeapPage.h
index 683c3dae182954ba7fbe09f3e69e5f5850027c02..16d5802f7be06bb7db0094c3ddbae002fb24980f 100644
--- a/third_party/WebKit/Source/platform/heap/HeapPage.h
+++ b/third_party/WebKit/Source/platform/heap/HeapPage.h
@@ -125,7 +125,7 @@ const uint8_t reuseForbiddenZapValue = 0x2c;
 
 class CallbackStack;
 class FreePagePool;
-class NormalPageHeap;
+class NormalPageArena;
 class OrphanedPagePool;
 class PageMemory;
 class PageMemoryRegion;
@@ -352,7 +352,7 @@ inline bool isPageHeaderAddress(Address address)
 class BasePage {
     DISALLOW_NEW_EXCEPT_PLACEMENT_NEW();
 public:
-    BasePage(PageMemory*, BaseHeap*);
+    BasePage(PageMemory*, BaseArena*);
     virtual ~BasePage() { }
 
     void link(BasePage** previousNext)
@@ -408,8 +408,8 @@ public:
 
     Address address() { return reinterpret_cast<Address>(this); }
     PageMemory* storage() const { return m_storage; }
-    BaseHeap* heap() const { return m_heap; }
-    bool orphaned() { return !m_heap; }
+    BaseArena* arena() const { return m_arena; }
+    bool orphaned() { return !m_arena; }
     bool terminating() { return m_terminating; }
     void setTerminating() { m_terminating = true; }
 
@@ -430,7 +430,7 @@ public:
 
 private:
     PageMemory* m_storage;
-    BaseHeap* m_heap;
+    BaseArena* m_arena;
     BasePage* m_next;
     // Whether the page is part of a terminating thread or not.
     bool m_terminating;
@@ -441,12 +441,12 @@ private:
     // Set to false at the start of a sweep, true  upon completion
     // of lazy sweeping.
     bool m_swept;
-    friend class BaseHeap;
+    friend class BaseArena;
 };
 
 class NormalPage final : public BasePage {
 public:
-    NormalPage(PageMemory*, BaseHeap*);
+    NormalPage(PageMemory*, BaseArena*);
 
     Address payload()
     {
@@ -492,7 +492,7 @@ public:
     }
 
 
-    NormalPageHeap* heapForNormalPage();
+    NormalPageArena* heapForNormalPage();
 
 private:
     HeapObjectHeader* findHeaderFromAddress(Address);
@@ -509,7 +509,7 @@ private:
 // object.
 class LargeObjectPage final : public BasePage {
 public:
-    LargeObjectPage(PageMemory*, BaseHeap*, size_t);
+    LargeObjectPage(PageMemory*, BaseArena*, size_t);
 
     Address payload() { return heapObjectHeader()->payload(); }
     size_t payloadSize() { return m_payloadSize; }
@@ -646,21 +646,21 @@ private:
     // All FreeListEntries in the nth list have size >= 2^n.
     FreeListEntry* m_freeLists[blinkPageSizeLog2];
 
-    friend class NormalPageHeap;
+    friend class NormalPageArena;
 };
 
 // Each thread has a number of thread heaps (e.g., Generic heaps,
 // typed heaps for Node, heaps for collection backings etc)
-// and BaseHeap represents each thread heap.
+// and BaseArena represents each thread heap.
 //
-// BaseHeap is a parent class of NormalPageHeap and LargeObjectHeap.
-// NormalPageHeap represents a heap that contains NormalPages
-// and LargeObjectHeap represents a heap that contains LargeObjectPages.
-class PLATFORM_EXPORT BaseHeap {
-    USING_FAST_MALLOC(BaseHeap);
+// BaseArena is a parent class of NormalPageArena and LargeObjectArena.
+// NormalPageArena represents a heap that contains NormalPages
+// and LargeObjectArena represents a heap that contains LargeObjectPages.
+class PLATFORM_EXPORT BaseArena {
+    USING_FAST_MALLOC(BaseArena);
 public:
-    BaseHeap(ThreadState*, int);
-    virtual ~BaseHeap();
+    BaseArena(ThreadState*, int);
+    virtual ~BaseArena();
     void cleanupPages();
 
     void takeSnapshot(const String& dumpBaseName, ThreadState::GCSnapshotInfo&);
@@ -688,7 +688,7 @@ public:
     void completeSweep();
 
     ThreadState* threadState() { return m_threadState; }
-    int heapIndex() const { return m_index; }
+    int arenaIndex() const { return m_index; }
 
 protected:
     BasePage* m_firstPage;
@@ -704,9 +704,9 @@ private:
     int m_index;
 };
 
-class PLATFORM_EXPORT NormalPageHeap final : public BaseHeap {
+class PLATFORM_EXPORT NormalPageArena final : public BaseArena {
 public:
-    NormalPageHeap(ThreadState*, int);
+    NormalPageArena(ThreadState*, int);
     void addToFreeList(Address address, size_t size)
     {
         ASSERT(findPageFromAddress(address));
@@ -759,9 +759,9 @@ private:
     size_t m_promptlyFreedSize;
 };
 
-class LargeObjectHeap final : public BaseHeap {
+class LargeObjectArena final : public BaseArena {
 public:
-    LargeObjectHeap(ThreadState*, int);
+    LargeObjectArena(ThreadState*, int);
     Address allocateLargeObjectPage(size_t, size_t gcInfoIndex);
     void freeLargeObjectPage(LargeObjectPage*);
 #if ENABLE(ASSERT)
@@ -872,7 +872,7 @@ void HeapObjectHeader::markDead()
     m_encoded |= headerDeadBitMask;
 }
 
-inline Address NormalPageHeap::allocateObject(size_t allocationSize, size_t gcInfoIndex)
+inline Address NormalPageArena::allocateObject(size_t allocationSize, size_t gcInfoIndex)
 {
     if (LIKELY(allocationSize <= m_remainingAllocationSize)) {
         Address headerAddress = m_currentAllocationPoint;