[profiler] Add two CpuProfileNode API functions to allow thread safe access to the node.

test/cctest/test-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 1653 matching lines @@
   profile->Delete();
   cpu_profiler->Dispose();
 }
 
 static void CheckFunctionDetails(v8::Isolate* isolate,
                                  const v8::CpuProfileNode* node,
                                  const char* name, const char* script_name,
                                  int script_id, int line, int column) {
   v8::Local<v8::Context> context = isolate->GetCurrentContext();
   CHECK(v8_str(name)->Equals(context, node->GetFunctionName()).FromJust());
+  CHECK_EQ(0, strcmp(name, node->GetFunctionNameStr()));
   CHECK(v8_str(script_name)
             ->Equals(context, node->GetScriptResourceName())
             .FromJust());
+  CHECK_EQ(0, strcmp(script_name, node->GetScriptResourceNameStr()));
   CHECK_EQ(script_id, node->GetScriptId());
   CHECK_EQ(line, node->GetLineNumber());
   CHECK_EQ(column, node->GetColumnNumber());
 }
 
 
 TEST(FunctionDetails) {
   i::FLAG_allow_natives_syntax = true;
   v8::HandleScope scope(CcTest::isolate());
   v8::Local<v8::Context> env = CcTest::NewContext(PROFILER_EXTENSION);
@@ skipping 396 matching lines @@
   iprofile->Print();
   v8::CpuProfile* profile = reinterpret_cast<v8::CpuProfile*>(iprofile);
 
   const char* branch[] = {"", "test"};
   const ProfileNode* itest_node =
       GetSimpleBranch(env, profile, branch, arraysize(branch));
   CHECK_EQ(0U, itest_node->deopt_infos().size());
 
   iprofiler->DeleteProfile(iprofile);
 }