Cleanup extra initialization of TickSample fields.

src/cpu-profiler.cc

 // Copyright 2010 the V8 project authors. 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 168 matching lines @@
   events_buffer_.Enqueue(evt_rec);
 }
 
 
 void ProfilerEventsProcessor::AddCurrentStack() {
   TickSampleEventRecord record;
   TickSample* sample = &record.sample;
   Isolate* isolate = Isolate::Current();
   sample->state = isolate->current_vm_state();
   sample->pc = reinterpret_cast<Address>(sample);  // Not NULL.
-  sample->tos = NULL;
-  sample->has_external_callback = false;
-  sample->frames_count = 0;
   for (StackTraceFrameIterator it(isolate);
        !it.done() && sample->frames_count < TickSample::kMaxFramesCount;
        it.Advance()) {
     sample->stack[sample->frames_count++] = it.frame()->pc();
   }
   record.order = enqueue_order_;
   ticks_from_vm_buffer_.Enqueue(record);
 }
 
 
@@ skipping 397 matching lines @@
 #ifdef ENABLE_LOGGING_AND_PROFILING
   Isolate* isolate = Isolate::Current();
   if (isolate->cpu_profiler() != NULL) {
     delete isolate->cpu_profiler();
   }
   isolate->set_cpu_profiler(NULL);
 #endif
 }
 
 } }  // namespace v8::internal