Revert of Removing "using" declarations that import names in the C++ Standard library.

Source/bindings/v8/custom/V8CSSStyleDeclarationCustom.cpp

Index: Source/bindings/v8/custom/V8CSSStyleDeclarationCustom.cpp
diff --git a/Source/bindings/v8/custom/V8CSSStyleDeclarationCustom.cpp b/Source/bindings/v8/custom/V8CSSStyleDeclarationCustom.cpp
index 10ee2e49e3e447500a3b68254408a7a1a5189109..a9cc9234c0f4fd8a542ef160c94df08a79ea968b 100644
--- a/Source/bindings/v8/custom/V8CSSStyleDeclarationCustom.cpp
+++ b/Source/bindings/v8/custom/V8CSSStyleDeclarationCustom.cpp
@@ -49,6 +49,7 @@
 #include "wtf/text/StringConcatenate.h"
 
 using namespace WTF;
+using namespace std;
 
 namespace WebCore {
 
@@ -164,7 +165,7 @@
             if (RuntimeCSSEnabled::isCSSPropertyEnabled(propertyId))
                 propertyNames.append(getJSPropertyName(propertyId));
         }
-        std::sort(propertyNames.begin(), propertyNames.end(), codePointCompareLessThan);
+        sort(propertyNames.begin(), propertyNames.end(), codePointCompareLessThan);
         propertyNamesLength = propertyNames.size();
     }