Support idle time in CPU profiler

src/profile-generator.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 596 matching lines @@
                                         line_number);
   code_entries_.Add(code_entry);
   return code_entry;
 }
 
 
 const char* const ProfileGenerator::kAnonymousFunctionName =
     "(anonymous function)";
 const char* const ProfileGenerator::kProgramEntryName =
     "(program)";
+const char* const ProfileGenerator::kIdleEntryName =
+    "(idle)";
 const char* const ProfileGenerator::kGarbageCollectorEntryName =
     "(garbage collector)";
 const char* const ProfileGenerator::kUnresolvedFunctionName =
     "(unresolved function)";
 
 
 ProfileGenerator::ProfileGenerator(CpuProfilesCollection* profiles)
     : profiles_(profiles),
       program_entry_(
           profiles->NewCodeEntry(Logger::FUNCTION_TAG, kProgramEntryName)),
+      idle_entry_(
+          profiles->NewCodeEntry(Logger::FUNCTION_TAG, kIdleEntryName)),
       gc_entry_(
           profiles->NewCodeEntry(Logger::BUILTIN_TAG,
                                  kGarbageCollectorEntryName)),
       unresolved_entry_(
           profiles->NewCodeEntry(Logger::FUNCTION_TAG,
                                  kUnresolvedFunctionName)) {
 }
 
 
 void ProfileGenerator::RecordTickSample(const TickSample& sample) {
@@ skipping 66 matching lines @@
     if (no_symbolized_entries) {
       *entry++ = EntryForVMState(sample.state);
     }
   }
 
   profiles_->AddPathToCurrentProfiles(entries);
 }
 
 
 } }  // namespace v8::internal