Replace ASSERT and ASSERT_NOT_REACHED with DCHECK and NOTREACHED in core/testing/.

third_party/WebKit/Source/core/testing/GCObservation.cpp

 /*
  * Copyright (C) 2013 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 20 matching lines @@
 #include "core/testing/GCObservation.h"
 
 namespace blink {
 
 static void setWeakCallbackForGCObservation(
     const v8::WeakCallbackInfo<GCObservation>& data) {
   data.GetParameter()->setWasCollected();
 }
 
 void GCObservation::setWasCollected() {
-  ASSERT(!wasCollected());
+  DCHECK(!wasCollected());
   m_observed.clear();
   m_collected = true;
 }
 
 GCObservation::GCObservation(v8::Local<v8::Value> observedValue)
     : m_observed(v8::Isolate::GetCurrent(), observedValue), m_collected(false) {
   m_observed.setWeak(this, setWeakCallbackForGCObservation);
 }
 
 }  // namespace blink