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

third_party/WebKit/Source/core/testing/DummyPageHolder.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 81 matching lines @@
   m_page->willBeDestroyed();
   m_page.clear();
   m_frame.clear();
 }
 
 Page& DummyPageHolder::page() const {
   return *m_page;
 }
 
 LocalFrame& DummyPageHolder::frame() const {
-  ASSERT(m_frame);
+  DCHECK(m_frame);
   return *m_frame;
 }
 
 FrameView& DummyPageHolder::frameView() const {
   return *m_frame->view();
 }
 
 Document& DummyPageHolder::document() const {
   return *m_frame->domWindow()->document();
 }
 
 }  // namespace blink