Split up leak detector into two stages for better leak reporting.

third_party/WebKit/public/web/WebLeakDetector.h

 /*
  * Copyright (C) 2014 Google Inc. 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
@@ skipping 44 matching lines @@
 
 class WebLeakDetector {
 public:
     virtual ~WebLeakDetector() { }
 
     BLINK_EXPORT static WebLeakDetector* create(WebLeakDetectorClient*);
 
     // Cleans up the DOM objects and counts them. |WebLeakDetectorClient::onLeakDetectionComplete()| is called when done.
     // This is supposed to be used for detecting DOM-object leaks.
     virtual void collectGarbageAndGetDOMCounts(WebLocalFrame*) = 0;
+
+    // Delay final round of garbage collections rounds, allowing instead
+    // the caller to manually start those using collectFinalGarbage().
+    virtual void delayFinalGarbageCollection() = 0;
+
+    virtual void collectFinalGarbage() = 0;
 };
 
 } // namespace blink
 
 #endif // WebLeakDetector_h