Add CollectSample API function to CpuProfiler

include/v8-profiler.h

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_V8_PROFILER_H_
 #define V8_V8_PROFILER_H_
 
 #include <vector>
 #include "v8.h"  // NOLINT(build/include)
 
@@ skipping 189 matching lines @@
    */
   void StartProfiling(Local<String> title, bool record_samples = false);
 
   /**
    * Stops collecting CPU profile with a given title and returns it.
    * If the title given is empty, finishes the last profile started.
    */
   CpuProfile* StopProfiling(Local<String> title);
 
   /**
+   * Force collection of a sample. Must be called on the VM thread.
+   * Recording the forced sample does not contribute to the aggregated
+   * profile statistics.
+   */
+  void CollectSample();
+
+  /**
    * Tells the profiler whether the embedder is idle.
    */
   void SetIdle(bool is_idle);
 
  private:
   CpuProfiler();
   ~CpuProfiler();
   CpuProfiler(const CpuProfiler&);
   CpuProfiler& operator=(const CpuProfiler&);
 };
@@ skipping 546 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_