Fix CPU profiler crash in start / stop sequence when non-existent name is passed

src/cpu-profiler.h

Index: src/cpu-profiler.h
diff --git a/src/cpu-profiler.h b/src/cpu-profiler.h
index 03b81764851cea6881e33a4d42cdbd130ecaab51..4d5559e4febdc9de02a7ca105e007347a6686170 100644
--- a/src/cpu-profiler.h
+++ b/src/cpu-profiler.h
@@ -260,7 +260,7 @@ class CpuProfiler {
   void StartProcessorIfNotStarted();
   CpuProfile* StopCollectingProfile(const char* title);
   CpuProfile* StopCollectingProfile(Object* security_token, String* title);
-  void StopProcessorIfLastProfile();
+  void StopProcessorIfLastProfile(const char* title);
 
   CpuProfilesCollection* profiles_;
   unsigned next_profile_uid_;