Expose TickSample and its APIs in v8-profiler.h

src/profiler/circular-queue.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_PROFILER_CIRCULAR_QUEUE_H_
 #define V8_PROFILER_CIRCULAR_QUEUE_H_
 
 #include "src/base/atomicops.h"
 #include "src/globals.h"
 
@@ skipping 13 matching lines @@
   // Executed on the application thread.
   SamplingCircularQueue();
   ~SamplingCircularQueue();
 
   // StartEnqueue returns a pointer to a memory location for storing the next
   // record or NULL if all entries are full at the moment.
   T* StartEnqueue();
   // Notifies the queue that the producer has complete writing data into the
   // memory returned by StartEnqueue and it can be passed to the consumer.
   void FinishEnqueue();
+  // Returns the current memory for enqueue.
+  T* CurrentEnqueue();
 
   // Executed on the consumer (analyzer) thread.
   // Retrieves, but does not remove, the head of this queue, returning NULL
   // if this queue is empty. After the record had been read by a consumer,
   // Remove must be called.
   T* Peek();
   void Remove();
 
  private:
   // Reserved values for the entry marker.
@@ skipping 16 matching lines @@
   V8_ALIGNED(PROCESSOR_CACHE_LINE_SIZE) Entry* dequeue_pos_;
 
   DISALLOW_COPY_AND_ASSIGN(SamplingCircularQueue);
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_PROFILER_CIRCULAR_QUEUE_H_