Combine two validUnit calls

Source/core/css/parser/CSSPropertyParser.cpp

Index: Source/core/css/parser/CSSPropertyParser.cpp
diff --git a/Source/core/css/parser/CSSPropertyParser.cpp b/Source/core/css/parser/CSSPropertyParser.cpp
index ba9e52de3088d5eb98918313428c738a35e50915..ce3f4b5a9844fe9331cf8b5eae8189617ebd50aa 100644
--- a/Source/core/css/parser/CSSPropertyParser.cpp
+++ b/Source/core/css/parser/CSSPropertyParser.cpp
@@ -1016,11 +1016,8 @@ bool CSSPropertyParser::parseValue(CSSPropertyID propId, bool important)
         return true;
     }
     case CSSPropertyTabSize:
-        // May be specified as a unit-less non-negative integer indicating number of space characters...
-        validPrimitive = validUnit(value, FInteger | FNonNeg);
-        // ... or as a Length.
-        if (!validPrimitive)
-            validPrimitive = validUnit(value, FLength | FNonNeg);
+        // May be specified as a unit-less non-negative integer or length indicating number of space characters.
+        validPrimitive = validUnit(value, FInteger | FLength | FNonNeg);
         break;
     case CSSPropertyBorderRadius:
     case CSSPropertyWebkitBorderRadius: