Fix trailing whitespace in .cpp, .h, and .idl files

Source/core/css/CSSGroupingRule.cpp

Index: Source/core/css/CSSGroupingRule.cpp
diff --git a/Source/core/css/CSSGroupingRule.cpp b/Source/core/css/CSSGroupingRule.cpp
index f41c1861b9cfd3563ff46692c7741bbd4a75a1c3..0d62e42d7b04068fba8eb9dc63d267d3e5f9e452 100644
--- a/Source/core/css/CSSGroupingRule.cpp
+++ b/Source/core/css/CSSGroupingRule.cpp
@@ -126,12 +126,12 @@ void CSSGroupingRule::appendCssTextForItems(StringBuilder& result) const
 }
 
 unsigned CSSGroupingRule::length() const
-{ 
-    return m_groupRule->childRules().size(); 
+{
+    return m_groupRule->childRules().size();
 }
 
 CSSRule* CSSGroupingRule::item(unsigned index) const
-{ 
+{
     if (index >= length())
         return 0;
     ASSERT(m_childRuleCSSOMWrappers.size() == m_groupRule->childRules().size());