Add timestamps to CPU profile samples.

include/v8-profiler.h

 // 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 88 matching lines @@
  */
 class V8_EXPORT CpuProfile {
  public:
   /** Returns CPU profile title. */
   Handle<String> GetTitle() const;
 
   /** Returns the root node of the top down call tree. */
   const CpuProfileNode* GetTopDownRoot() const;
 
   /**
-    * Returns number of samples recorded. The samples are not recorded unless
-    * |record_samples| parameter of CpuProfiler::StartCpuProfiling is true.
-    */
+   * Returns number of samples recorded. The samples are not recorded unless
+   * |record_samples| parameter of CpuProfiler::StartCpuProfiling is true.
+   */
   int GetSamplesCount() const;
 
   /**
-    * Returns profile node corresponding to the top frame the sample at
-    * the given index.
-    */
+   * Returns profile node corresponding to the top frame the sample at
+   * the given index.
+   */
   const CpuProfileNode* GetSample(int index) const;
 
   /**
-    * Returns time when the profile recording was started (in microseconds)
-    * since some unspecified starting point.
-    */
+   * Returns the timestamp of the sample. The timestamp is the number of
+   * microseconds since some unspecified starting point.
+   * The point is equal to the starting point used by GetStartTime.
+   */
+  int64_t GetSampleTimestamp(int index) const;
+
+  /**
+   * Returns time when the profile recording was started (in microseconds)
+   * since some unspecified starting point.
+   */
   int64_t GetStartTime() const;
 
   /**
-    * Returns time when the profile recording was stopped (in microseconds)
-    * since some unspecified starting point. The point is however equal to the
-    * starting point used by GetStartTime.
-    */
+   * Returns time when the profile recording was stopped (in microseconds)
+   * since some unspecified starting point.
+   * The point is equal to the starting point used by GetStartTime.
+   */
   int64_t GetEndTime() const;
 
   /**
    * Deletes the profile and removes it from CpuProfiler's list.
    * All pointers to nodes previously returned become invalid.
    */
   void Delete();
 };
 
 
@@ skipping 476 matching lines @@
   uint32_t index;  // Index of the time interval that was changed.
   uint32_t count;  // New value of count field for the interval with this index.
   uint32_t size;  // New value of size field for the interval with this index.
 };
 
 
 }  // namespace v8
 
 
 #endif  // V8_V8_PROFILER_H_