Replace ASSERT()s with DCHECK*() in core/html/*.{cpp,h}.

third_party/WebKit/Source/core/html/HTMLSourceElement.cpp

 /*
  * Copyright (C) 2007, 2008, 2010 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 131 matching lines @@
 }
 
 void HTMLSourceElement::cancelPendingErrorEvent()
 {
     DVLOG(SOURCE_LOG_LEVEL) << "cancelPendingErrorEvent - " << (void*)this;
     sourceErrorEventSender().cancelEvent(this);
 }
 
 void HTMLSourceElement::dispatchPendingEvent(SourceEventSender* eventSender)
 {
-    ASSERT_UNUSED(eventSender, eventSender == &sourceErrorEventSender());
+    DCHECK_EQ(eventSender, &sourceErrorEventSender());
     DVLOG(SOURCE_LOG_LEVEL) << "dispatchPendingEvent - " << (void*)this;
     dispatchEvent(Event::createCancelable(EventTypeNames::error));
 }
 
 bool HTMLSourceElement::mediaQueryMatches() const
 {
     if (!m_mediaQueryList)
         return true;
 
     return m_mediaQueryList->matches();
@@ skipping 24 matching lines @@
 }
 
 DEFINE_TRACE(HTMLSourceElement)
 {
     visitor->trace(m_mediaQueryList);
     visitor->trace(m_listener);
     HTMLElement::trace(visitor);
 }
 
 } // namespace blink