Allow configuring CPU profiler sampling interval using public API

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 123 matching lines @@
 };
 
 
 /**
  * Interface for controlling CPU profiling. Instance of the
  * profiler can be retrieved using v8::Isolate::GetCpuProfiler.
  */
 class V8_EXPORT CpuProfiler {
  public:
   /**
-   * A note on security tokens usage. As scripts from different
-   * origins can run inside a single V8 instance, it is possible to
-   * have functions from different security contexts intermixed in a
-   * single CPU profile. To avoid exposing function names belonging to
-   * other contexts, filtering by security token is performed while
-   * obtaining profiling results.
+   * Changes default CPU profiler sampling interval to the specified number
+   * of microseconds. Default interval is 1000us. This method must be called
+   * when there are no profiles being recorded.
    */
+  void SetSamplingInterval(int us);
 
   /**
    * Returns the number of profiles collected (doesn't include
    * profiles that are being collected at the moment of call.)
    */
   int GetProfileCount();
 
   /** Returns a profile by index. */
   const CpuProfile* GetCpuProfile(int index);
 
@@ skipping 399 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_