Simplify ProfLazyMode test on Linux.

src/platform-macos.cc

 // Copyright 2006-2008 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 616 matching lines @@
       reinterpret_cast<Sampler::PlatformData*>(arg);
   data->Runner();
   return 0;
 }
 
 
 Sampler::Sampler(int interval, bool profiling)
     : interval_(interval),
       profiling_(profiling),
       synchronous_(profiling),
-      active_(false) {
+      active_(false),
+      samples_taken_(0) {
   data_ = new PlatformData(this);
 }
 
 
 Sampler::~Sampler() {
   delete data_;
 }
 
 
 void Sampler::Start() {
@@ skipping 29 matching lines @@
 
   // Deallocate Mach port for thread.
   if (IsSynchronous()) {
     mach_port_deallocate(data_->task_self_, data_->profiled_thread_);
   }
 }
 
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
 } }  // namespace v8::internal