Reset old generation limit on main frame context disposal.

src/heap/gc-tracer.h

 // Copyright 2014 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_GC_TRACER_H_
 #define V8_HEAP_GC_TRACER_H_
 
 #include "src/base/platform/platform.h"
 
 namespace v8 {
@@ skipping 53 matching lines @@
     elements_[end_] = element;
     end_ = (end_ + 1) % (MAX_SIZE + 1);
     if (end_ == begin_) begin_ = (begin_ + 1) % (MAX_SIZE + 1);
   }
   void push_front(const T& element) {
     begin_ = (begin_ + MAX_SIZE) % (MAX_SIZE + 1);
     if (begin_ == end_) end_ = (end_ + MAX_SIZE) % (MAX_SIZE + 1);
     elements_[begin_] = element;
   }
 
+  void reset() {
+    begin_ = 0;
+    end_ = 0;
+  }
+
  private:
   T elements_[MAX_SIZE + 1];
   size_t begin_;
   size_t end_;
 
   DISALLOW_COPY_AND_ASSIGN(RingBuffer);
 };
 
 
 // GCTracer collects and prints ONE line after each garbage collector
@@ skipping 299 matching lines @@
   double ContextDisposalRateInMilliseconds() const;
 
   // Computes the average survival rate based on the last recorded survival
   // events.
   // Returns 0 if no events have been recorded.
   double AverageSurvivalRate() const;
 
   // Returns true if at least one survival event was recorded.
   bool SurvivalEventsRecorded() const;
 
+  // Discard all recorded survival events.
+  void ResetSurvivalEvents();
+
  private:
   // Print one detailed trace line in name=value format.
   // TODO(ernstm): Move to Heap.
   void PrintNVP() const;
 
   // Print one trace line.
   // TODO(ernstm): Move to Heap.
   void Print() const;
 
   // Compute the mean duration of the events in the given ring buffer.
@@ skipping 79 matching lines @@
 
   // Counts how many tracers were started without stopping.
   int start_counter_;
 
   DISALLOW_COPY_AND_ASSIGN(GCTracer);
 };
 }
 }  // namespace v8::internal
 
 #endif  // V8_HEAP_GC_TRACER_H_