Add sanity test for CPU profiler

src/platform-nullos.cc

 // Copyright 2012 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 351 matching lines @@
   PlatformData() {
     UNIMPLEMENTED();
   }
 
   void* pd_data_;
 };
 
 
 Thread::Thread(const Options& options)
     : data_(new PlatformData()),
-      stack_size_(options.stack_size) {
+      stack_size_(options.stack_size),
+      start_semaphore_(NULL) {
   set_name(options.name);
   UNIMPLEMENTED();
 }
 
 
 Thread::Thread(const char* name)
     : data_(new PlatformData()),
       stack_size_(0) {
   set_name(name);
   UNIMPLEMENTED();
@@ skipping 136 matching lines @@
   UNIMPLEMENTED();
 }
 
 
 void ProfileSampler::Stop() {
   UNIMPLEMENTED();
 }
 
 
 } }  // namespace v8::internal