[heap] Fix scavenger --trace-gc-nvp glitches.

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"
 #include "src/counters.h"
 #include "src/globals.h"
@@ skipping 386 matching lines @@
   // bytes/millisecond.
   // Returns 0 if no events have been recorded.
   intptr_t FinalIncrementalMarkCompactSpeedInBytesPerMillisecond() const;
 
   // Compute the overall mark compact speed including incremental steps
   // and the final mark-compact step.
   double CombinedMarkCompactSpeedInBytesPerMillisecond();
 
   // Allocation throughput in the new space in bytes/millisecond.
   // Returns 0 if no allocation events have been recorded.
-  size_t NewSpaceAllocationThroughputInBytesPerMillisecond(
+  double NewSpaceAllocationThroughputInBytesPerMillisecond(
       double time_ms = 0) const;
 
   // Allocation throughput in the old generation in bytes/millisecond in the
   // last time_ms milliseconds.
   // Returns 0 if no allocation events have been recorded.
-  size_t OldGenerationAllocationThroughputInBytesPerMillisecond(
+  double OldGenerationAllocationThroughputInBytesPerMillisecond(
       double time_ms = 0) const;
 
   // Allocation throughput in heap in bytes/millisecond in the last time_ms
   // milliseconds.
   // Returns 0 if no allocation events have been recorded.
-  size_t AllocationThroughputInBytesPerMillisecond(double time_ms) const;
+  double AllocationThroughputInBytesPerMillisecond(double time_ms) const;
 
   // Allocation throughput in heap in bytes/milliseconds in the last
   // kThroughputTimeFrameMs seconds.
   // Returns 0 if no allocation events have been recorded.
   size_t CurrentAllocationThroughputInBytesPerMillisecond() const;
 
   // Allocation throughput in old generation in bytes/milliseconds in the last
   // kThroughputTimeFrameMs seconds.
   // Returns 0 if no allocation events have been recorded.
   size_t CurrentOldGenerationAllocationThroughputInBytesPerMillisecond() const;
@@ skipping 150 matching lines @@
 
   // Separate timer used for --runtime_call_stats
   RuntimeCallTimer timer_;
 
   DISALLOW_COPY_AND_ASSIGN(GCTracer);
 };
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_GC_TRACER_H_