Make Range.detach() a no-op

Source/core/editing/EditingStyle.cpp

 /*
  * Copyright (C) 2007, 2008, 2009 Apple Computer, Inc.
  * Copyright (C) 2010, 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:
  * 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
@@ skipping 1250 matching lines @@
         return nullptr;
 
     RefPtr<EditingStyle> style = EditingStyle::create(element, EditingStyle::AllProperties);
     style->mergeTypingStyle(&element->document());
 
     // If background color is transparent, traverse parent nodes until we hit a different value or document root
     // Also, if the selection is a range, ignore the background color at the start of selection,
     // and find the background color of the common ancestor.
     if (shouldUseBackgroundColorInEffect && (selection.isRange() || hasTransparentBackgroundColor(style->m_mutableStyle.get()))) {
         RefPtrWillBeRawPtr<Range> range(selection.toNormalizedRange());
-        if (PassRefPtrWillBeRawPtr<CSSValue> value = backgroundColorInEffect(range->commonAncestorContainer(IGNORE_EXCEPTION)))
+        if (PassRefPtrWillBeRawPtr<CSSValue> value = backgroundColorInEffect(range->commonAncestorContainer()))
             style->setProperty(CSSPropertyBackgroundColor, value->cssText());
     }
 
     return style;
 }
 
 WritingDirection EditingStyle::textDirectionForSelection(const VisibleSelection& selection, EditingStyle* typingStyle, bool& hasNestedOrMultipleEmbeddings)
 {
     hasNestedOrMultipleEmbeddings = true;
 
@@ skipping 365 matching lines @@
 {
     for (Node* ancestor = node; ancestor; ancestor = ancestor->parentNode()) {
         RefPtr<CSSComputedStyleDeclaration> ancestorStyle = CSSComputedStyleDeclaration::create(ancestor);
         if (!hasTransparentBackgroundColor(ancestorStyle.get()))
             return ancestorStyle->getPropertyCSSValue(CSSPropertyBackgroundColor);
     }
     return nullptr;
 }
 
 }