Revert of [heap] Simplify heuristics for incremental step size.

src/heap/heap.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_HEAP_H_
 #define V8_HEAP_HEAP_H_
 
 #include <cmath>
 #include <map>
 
@@ skipping 1659 matching lines @@
 
   // Record statistics before and after garbage collection.
   void ReportStatisticsBeforeGC();
   void ReportStatisticsAfterGC();
 
   // Creates and installs the full-sized number string cache.
   int FullSizeNumberStringCacheLength();
   // Flush the number to string cache.
   void FlushNumberStringCache();
 
+  // TODO(hpayer): Allocation site pretenuring may make this method obsolete.
+  // Re-visit incremental marking heuristics.
+  bool IsHighSurvivalRate() { return high_survival_rate_period_length_ > 0; }
+
   void ConfigureInitialOldGenerationSize();
 
   bool HasLowYoungGenerationAllocationRate();
   bool HasLowOldGenerationAllocationRate();
   double YoungGenerationMutatorUtilization();
   double OldGenerationMutatorUtilization();
 
   void ReduceNewSpaceSize();
 
   bool TryFinalizeIdleIncrementalMarking(
@@ skipping 1031 matching lines @@
   friend class LargeObjectSpace;
   friend class NewSpace;
   friend class PagedSpace;
   DISALLOW_COPY_AND_ASSIGN(AllocationObserver);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_HEAP_H_