Combine two validUnit calls

Source/core/css/parser/CSSPropertyParser.cpp

 /*
  * Copyright (C) 2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Nicholas Shanks <webkit@nickshanks.com>
  * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2012 Adobe Systems Incorporated. All rights reserved.
  * Copyright (C) 2012 Intel Corporation. All rights reserved.
  *
@@ skipping 998 matching lines @@
             if (!validPrimitive)
                 return false;
             parsedValue2 = createPrimitiveNumericValue(value);
         } else
             parsedValue2 = parsedValue1;
 
         addProperty(propId, createPrimitiveValuePair(parsedValue1.release(), parsedValue2.release()), 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:
         return parseBorderRadius(propId, important);
     case CSSPropertyOutlineOffset:
         validPrimitive = validUnit(value, FLength);
         break;
     case CSSPropertyTextShadow: // CSS2 property, dropped in CSS2.1, back in CSS3, so treat as CSS3
     case CSSPropertyBoxShadow:
     case CSSPropertyWebkitBoxShadow:
@@ skipping 7483 matching lines @@
         }
     }
 
     if (!list->length())
         return nullptr;
 
     return list.release();
 }
 
 } // namespace blink