Refactor the Heap into ThreadHeap to prepare for per thread heaps

third_party/WebKit/Source/bindings/core/v8/V8GCController.cpp

 /*
  * Copyright (C) 2009 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 329 matching lines @@
         // This single GC is not enough for two reasons:
         //   (1) The GC is not precise because the GC scans on-stack pointers conservatively.
         //   (2) One GC is not enough to break a chain of persistent handles. It's possible that
         //       some heap allocated objects own objects that contain persistent handles
         //       pointing to other heap allocated objects. To break the chain, we need multiple GCs.
         //
         // Regarding (1), we force a precise GC at the end of the current event loop. So if you want
         // to collect all garbage, you need to wait until the next event loop.
         // Regarding (2), it would be OK in practice to trigger only one GC per gcEpilogue, because
         // GCController.collectAll() forces multiple V8's GC.
-        Heap::collectGarbage(BlinkGC::HeapPointersOnStack, BlinkGC::GCWithSweep, BlinkGC::ForcedGC);
+        ThreadHeap::collectGarbage(BlinkGC::HeapPointersOnStack, BlinkGC::GCWithSweep, BlinkGC::ForcedGC);
 
         // Forces a precise GC at the end of the current event loop.
         if (ThreadState::current()) {
             RELEASE_ASSERT(!ThreadState::current()->isInGC());
             ThreadState::current()->setGCState(ThreadState::FullGCScheduled);
         }
     }
 
     // v8::kGCCallbackFlagCollectAllAvailableGarbage is used when V8 handles
     // low memory notifications.
     if (flags & v8::kGCCallbackFlagCollectAllAvailableGarbage) {
         // This single GC is not enough. See the above comment.
-        Heap::collectGarbage(BlinkGC::HeapPointersOnStack, BlinkGC::GCWithSweep, BlinkGC::ForcedGC);
+        ThreadHeap::collectGarbage(BlinkGC::HeapPointersOnStack, BlinkGC::GCWithSweep, BlinkGC::ForcedGC);
 
         // Do not force a precise GC at the end of the current event loop.
         // According to UMA stats, the collection rate of the precise GC
         // scheduled at the end of the low memory handling is extremely low,
         // because the above conservative GC is sufficient for collecting
         // most objects. So we intentionally don't schedule a precise GC here.
     }
 
     TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"), "UpdateCounters", TRACE_EVENT_SCOPE_THREAD, "data", InspectorUpdateCountersEvent::data());
 }
@@ skipping 114 matching lines @@
 
     DEFINE_THREAD_SAFE_STATIC_LOCAL(CustomCountHistogram, scanPendingActivityHistogram, new CustomCountHistogram("Blink.ScanPendingActivityDuration", 1, 1000, 50));
     double startTime = WTF::currentTimeMS();
     PendingActivityVisitor visitor(executionContext);
     toIsolate(executionContext)->VisitHandlesWithClassIds(&visitor);
     scanPendingActivityHistogram.count(static_cast<int>(WTF::currentTimeMS() - startTime));
     return visitor.pendingActivityFound();
 }
 
 } // namespace blink