New heap profiler: add support for progress reporting and control.

include/v8.h

 // Copyright 2007-2009 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 3263 matching lines @@
   virtual OutputEncoding GetOutputEncoding() { return kAscii; }
   /**
    * Writes the next chunk of snapshot data into the stream. Writing
    * can be stopped by returning kAbort as function result. EndOfStream
    * will not be called in case writing was aborted.
    */
   virtual WriteResult WriteAsciiChunk(char* data, int size) = 0;
 };
 
 
+/**
+ * An interface for reporting progress and controlling long-running
+ * activities.
+ */
+class V8EXPORT ActivityControl {  // NOLINT
+ public:
+  enum ControlOption {
+    kContinue = 0,
+    kAbort = 1
+  };
+  virtual ~ActivityControl() {}
+  /**
+   * Notify about current progress. The activity can be stopped by
+   * returning kAbort as the callback result.
+   */
+  virtual ControlOption ReportProgressValue(int done, int total) = 0;
+};
+
 
 // --- I m p l e m e n t a t i o n ---
 
 
 namespace internal {
 
 static const int kApiPointerSize = sizeof(void*);  // NOLINT
 static const int kApiIntSize = sizeof(int);  // NOLINT
 
 // Tag information for HeapObject.
@@ skipping 450 matching lines @@
 
 
 }  // namespace v8
 
 
 #undef V8EXPORT
 #undef TYPE_CHECK
 
 
 #endif  // V8_H_