Add sanity test for CPU profiler

src/cpu-profiler.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 427 matching lines @@
 
 
 void CpuProfiler::StartProcessorIfNotStarted() {
   if (processor_ == NULL) {
     // Disable logging when using the new implementation.
     saved_logging_nesting_ = isolate_->logger()->logging_nesting_;
     isolate_->logger()->logging_nesting_ = 0;
     generator_ = new ProfileGenerator(profiles_);
     processor_ = new ProfilerEventsProcessor(generator_);
     is_profiling_ = true;
-    processor_->Start();
+    processor_->StartSynchronously();
     // Enumerate stuff we already have in the heap.
     if (isolate_->heap()->HasBeenSetUp()) {
       if (!FLAG_prof_browser_mode) {
         bool saved_log_code_flag = FLAG_log_code;
         FLAG_log_code = true;
         isolate_->logger()->LogCodeObjects();
         FLAG_log_code = saved_log_code_flag;
       }
       isolate_->logger()->LogCompiledFunctions();
       isolate_->logger()->LogAccessorCallbacks();
     }
     // Enable stack sampling.
     Sampler* sampler = reinterpret_cast<Sampler*>(isolate_->logger()->ticker_);
+    sampler->IncreaseProfilingDepth();
     if (!sampler->IsActive()) {
       sampler->Start();
       need_to_stop_sampler_ = true;
     }
-    sampler->IncreaseProfilingDepth();
   }
 }
 
 
 CpuProfile* CpuProfiler::StopProfiling(const char* title) {
   if (!is_profiling_) return NULL;
   const double actual_sampling_rate = generator_->actual_sampling_rate();
   StopProcessorIfLastProfile(title);
   CpuProfile* result =
       profiles_->StopProfiling(TokenEnumerator::kNoSecurityToken,
@@ skipping 34 matching lines @@
   processor_->Join();
   delete processor_;
   delete generator_;
   processor_ = NULL;
   generator_ = NULL;
   logger->logging_nesting_ = saved_logging_nesting_;
 }
 
 
 } }  // namespace v8::internal