Enable heap compaction on all 'container' arenas.

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

 /*
  * 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 486 matching lines @@
     normal_page->Unlink(&first_unswept_page_);
     normal_page->MarkAsSwept();
     // If not the first page, add |normalPage| onto the available pages chain.
     if (!context.current_page_)
       context.current_page_ = normal_page;
     else
       normal_page->Link(&context.available_pages_);
     normal_page->SweepAndCompact(context);
   }
 
+  // All pages were empty; nothing to compact.
+  if (!context.current_page_) {
+    heap.Compaction()->FinishedArenaCompaction(this, 0, 0);
+    return;
+  }
+
   size_t freed_size = 0;
   size_t freed_page_count = 0;
 
-  DCHECK(context.current_page_);
   // If the current page hasn't been allocated into, add it to the available
   // list, for subsequent release below.
   size_t allocation_point = context.allocation_point_;
   if (!allocation_point) {
     context.current_page_->Link(&context.available_pages_);
   } else {
     NormalPage* current_page = context.current_page_;
     current_page->Link(&first_page_);
     if (allocation_point != current_page->PayloadSize()) {
       // Put the remainder of the page onto the free list.
@@ skipping 1318 matching lines @@
 
   has_entries_ = true;
   size_t index = GetHash(address);
   DCHECK(!(index & 1));
   Address cache_page = RoundToBlinkPageStart(address);
   entries_[index + 1] = entries_[index];
   entries_[index] = cache_page;
 }
 
 }  // namespace blink