Simplify pre+post GC ThreadState steps.

third_party/WebKit/Source/platform/heap/ThreadState.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 1450 matching lines @@
       double startTime = WTF::currentTimeMS();
 
       if (gcType == BlinkGC::TakeSnapshot)
         BlinkGCMemoryDumpProvider::instance()->clearProcessDumpForCurrentGC();
 
       // Disallow allocation during garbage collection (but not during the
       // finalization that happens when the visitorScope is torn down).
       NoAllocationScope noAllocationScope(this);
 
       heap().commitCallbackStacks();
-      heap().preGC();
+      preGC();
 
       StackFrameDepthScope stackDepthScope(&heap().stackFrameDepth());
 
       size_t totalObjectSize = heap().heapStats().allocatedObjectSize() +
                                heap().heapStats().markedObjectSize();
       if (gcType != BlinkGC::TakeSnapshot)
         heap().resetHeapCounters();
 
       {
         // 1. Trace persistent roots.
@@ skipping 45 matching lines @@
           EnumerationHistogram, gcReasonHistogram,
           new EnumerationHistogram("BlinkGC.GCReason",
                                    BlinkGC::LastGCReason + 1));
       gcReasonHistogram.count(reason);
 
       heap().m_lastGCReason = reason;
 
       ThreadHeap::reportMemoryUsageHistogram();
       WTF::Partitions::reportMemoryUsageHistogram();
     }
-    heap().postGC(gcType);
+    postGC(gcType);
   }
 
-  heap().preSweep(gcType);
+  preSweep(gcType);
   heap().decommitCallbackStacks();
 }
 
 void ThreadState::collectAllGarbage() {
   // We need to run multiple GCs to collect a chain of persistent handles.
   size_t previousLiveObjects = 0;
   for (int i = 0; i < 5; ++i) {
     collectGarbage(BlinkGC::NoHeapPointersOnStack, BlinkGC::GCWithSweep,
                    BlinkGC::ForcedGC);
     size_t liveObjects = heap().heapStats().markedObjectSize();
     if (liveObjects == previousLiveObjects)
       break;
     previousLiveObjects = liveObjects;
   }
 }
 
 }  // namespace blink