Oilpan: simplify away StoppingOtherThreads pseudo GCState.

Source/platform/heap/ThreadState.h

 /*
  * 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 178 matching lines @@
         GCWithoutSweep, // Lazy sweeping is scheduled.
         ThreadTerminationGC, // A thread-local GC scheduled before the thread shutdown.
     };
 
     // See setGCState() for possible state transitions.
     enum GCState {
         NoGCScheduled,
         IdleGCScheduled,
         PreciseGCScheduled,
         FullGCScheduled,
-        StoppingOtherThreads,
         GCRunning,
         EagerSweepScheduled,
         LazySweepScheduled,
         Sweeping,
         SweepingAndIdleGCScheduled,
         SweepingAndPreciseGCScheduled,
     };
 
     // The NoAllocationScope class is used in debug mode to catch unwanted
     // allocations. E.g. allocations during GC.
@@ skipping 139 matching lines @@
     void completeSweep();
     void postSweep();
 
     // Support for disallowing allocation. Mainly used for sanity
     // checks asserts.
     bool isAllocationAllowed() const { return !isAtSafePoint() && !m_noAllocationCount; }
     void enterNoAllocationScope() { m_noAllocationCount++; }
     void leaveNoAllocationScope() { m_noAllocationCount--; }
     bool isGCForbidden() const { return m_gcForbiddenCount; }
     void enterGCForbiddenScope() { m_gcForbiddenCount++; }
-    void leaveGCForbiddenScope() { m_gcForbiddenCount--; }
+    void leaveGCForbiddenScope()
+    {
+        ASSERT(m_gcForbiddenCount > 0);
+        m_gcForbiddenCount--;
+    }
     bool sweepForbidden() const { return m_sweepForbidden; }
 
     void prepareRegionTree();
     void flushHeapDoesNotContainCacheIfNeeded();
 
     // Safepoint related functionality.
     //
     // When a thread attempts to perform GC it needs to stop all other threads
     // that use the heap or at least guarantee that they will not touch any
     // heap allocated object until GC is complete.
@@ skipping 186 matching lines @@
     // constructed.
     void enterGCForbiddenScopeIfNeeded(GarbageCollectedMixinConstructorMarker* gcMixinMarker)
     {
         if (!m_gcMixinMarker) {
             enterGCForbiddenScope();
             m_gcMixinMarker = gcMixinMarker;
         }
     }
     void leaveGCForbiddenScopeIfNeeded(GarbageCollectedMixinConstructorMarker* gcMixinMarker)
     {
-        ASSERT(m_gcForbiddenCount > 0);
         if (m_gcMixinMarker == gcMixinMarker) {
             leaveGCForbiddenScope();
             m_gcMixinMarker = nullptr;
         }
     }
 
     // vectorBackingHeap() returns a heap that the vector allocation should use.
     // We have four vector heaps and want to choose the best heap here.
     //
     // The goal is to improve the succession rate where expand and
@@ skipping 165 matching lines @@
 };
 
 template<> class ThreadStateFor<AnyThread> {
 public:
     static ThreadState* state() { return ThreadState::current(); }
 };
 
 } // namespace blink
 
 #endif // ThreadState_h