Replace ASSERT with DCHECK in core/

third_party/WebKit/Source/core/frame/VisualViewport.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 424 matching lines @@
       is_horizontal ? web_overlay_scrollbar_horizontal_
                     : web_overlay_scrollbar_vertical_;
 
   ScrollbarThemeOverlay& theme = ScrollbarThemeOverlay::MobileTheme();
   int thumb_thickness = theme.ThumbThickness();
   int scrollbar_thickness = theme.ScrollbarThickness(kRegularScrollbar);
   int scrollbar_margin = theme.ScrollbarMargin();
 
   if (!web_scrollbar_layer) {
     ScrollingCoordinator* coordinator = GetPage().GetScrollingCoordinator();
-    ASSERT(coordinator);
+    DCHECK(coordinator);
     ScrollbarOrientation webcore_orientation =
         is_horizontal ? kHorizontalScrollbar : kVerticalScrollbar;
     web_scrollbar_layer = coordinator->CreateSolidColorScrollbarLayer(
         webcore_orientation, thumb_thickness, scrollbar_margin, false);
 
     // The compositor will control the scrollbar's visibility. Set to invisible
     // by default so scrollbars don't show up in layout tests.
     web_scrollbar_layer->Layer()->SetOpacity(0);
     scrollbar_graphics_layer->SetContentsToPlatformLayer(
         web_scrollbar_layer->Layer());
@@ skipping 400 matching lines @@
   } else if (graphics_layer == root_transform_layer_.get()) {
     name = "Root Transform Layer";
   } else {
     NOTREACHED();
   }
 
   return name;
 }
 
 }  // namespace blink