Revert of Prepare for multiple ThreadHeaps

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

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "platform/heap/PagePool.h"
 
 #include "platform/heap/Heap.h"
 #include "platform/heap/PageMemory.h"
 #include "wtf/Assertions.h"
 
@@ skipping 59 matching lines @@
 {
     page->markOrphaned();
     PoolEntry* entry = new PoolEntry(page, m_pool[index]);
     m_pool[index] = entry;
 }
 
 NO_SANITIZE_ADDRESS
 void OrphanedPagePool::decommitOrphanedPages()
 {
     ASSERT(ThreadState::current()->isInGC());
-    ASSERT(ThreadState::current()->heap().isAtSafePoint());
+
+#if ENABLE(ASSERT)
+    // No locking needed as all threads are at safepoints at this point in time.
+    for (ThreadState* state : ThreadState::attachedThreads())
+        ASSERT(state->isAtSafePoint());
+#endif
 
     for (int index = 0; index < BlinkGC::NumberOfArenas; ++index) {
         PoolEntry* entry = m_pool[index];
         PoolEntry** prevNext = &m_pool[index];
         while (entry) {
             BasePage* page = entry->data;
             // Check if we should reuse the memory or just free it.
             // Large object memory is not reused but freed, normal blink heap
             // pages are reused.
             // NOTE: We call the destructor before freeing or adding to the
             // free page pool.
             PageMemory* memory = page->storage();
             if (page->isLargeObjectPage()) {
                 page->~BasePage();
                 delete memory;
             } else {
                 page->~BasePage();
                 clearMemory(memory);
-                ThreadHeap::mainThreadHeap()->getFreePagePool()->addFreePage(index, memory);
+                ThreadHeap::getFreePagePool()->addFreePage(index, memory);
             }
 
             PoolEntry* deadEntry = entry;
             entry = entry->next;
             *prevNext = entry;
             delete deadEntry;
         }
     }
 }
 
@@ skipping 29 matching lines @@
             BasePage* page = entry->data;
             if (page->contains(reinterpret_cast<Address>(object)))
                 return true;
         }
     }
     return false;
 }
 #endif
 
 } // namespace blink