RELEASE_ASSERT -> CHECK and ASSERT -> DCHECK in web.

third_party/WebKit/Source/web/mac/WebSubstringUtil.mm

 /*
  * Copyright (C) 2005, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2011 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.
@@ skipping 54 matching lines @@
     size_t length = range.endPosition().computeOffsetInContainerNode() - range.startPosition().computeOffsetInContainerNode();
 
     unsigned position = 0;
     for (TextIterator it(range.startPosition(), range.endPosition()); !it.atEnd() && [string length] < length; it.advance()) {
         unsigned numCharacters = it.length();
         if (!numCharacters)
             continue;
 
         Node* container = it.currentContainer();
         LayoutObject* layoutObject = container->layoutObject();
-        ASSERT(layoutObject);
+        DCHECK(layoutObject);
         if (!layoutObject)
             continue;
 
         const ComputedStyle* style = layoutObject->style();
         const FontPlatformData& fontPlatformData = style->font().primaryFont()->platformData();
         NSFont* font = toNSFont(fontPlatformData.ctFont());
         // If the platform font can't be loaded, or the size is incorrect comparing
         // to the computed style, it's likely that the site is using a web font.
         // For now, just use the default font instead.
         // TODO(rsesek): Change the font activation flags to allow other processes
@@ skipping 84 matching lines @@
     if (ephemeralRange.isNull())
         return nil;
 
     NSAttributedString* result = attributedSubstringFromRange(ephemeralRange);
     if (baselinePoint)
         *baselinePoint = getBaselinePoint(frame->view(), ephemeralRange, result);
     return result;
 }
 
 } // namespace blink