Add timestamps to CPU profile samples.

src/api.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 7049 matching lines @@
   return reinterpret_cast<const CpuProfileNode*>(profile->top_down()->root());
 }
 
 
 const CpuProfileNode* CpuProfile::GetSample(int index) const {
   const i::CpuProfile* profile = reinterpret_cast<const i::CpuProfile*>(this);
   return reinterpret_cast<const CpuProfileNode*>(profile->sample(index));
 }
 
 
+int64_t CpuProfile::GetSampleTimestamp(int index) const {
+  const i::CpuProfile* profile = reinterpret_cast<const i::CpuProfile*>(this);
+  return (profile->sample_timestamp(index) - i::TimeTicks()).InMicroseconds();
+}
+
+
 int64_t CpuProfile::GetStartTime() const {
   const i::CpuProfile* profile = reinterpret_cast<const i::CpuProfile*>(this);
   return (profile->start_time() - i::TimeTicks()).InMicroseconds();
 }
 
 
 int64_t CpuProfile::GetEndTime() const {
   const i::CpuProfile* profile = reinterpret_cast<const i::CpuProfile*>(this);
   return (profile->end_time() - i::TimeTicks()).InMicroseconds();
 }
@@ skipping 518 matching lines @@
   Isolate* isolate = reinterpret_cast<Isolate*>(info.GetIsolate());
   Address callback_address =
       reinterpret_cast<Address>(reinterpret_cast<intptr_t>(callback));
   VMState<EXTERNAL> state(isolate);
   ExternalCallbackScope call_scope(isolate, callback_address);
   callback(info);
 }
 
 
 } }  // namespace v8::internal