Don't handle unitless length quirk in CSS parser fast path

third_party/WebKit/Source/core/css/parser/CSSParserFastPaths.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/css/parser/CSSParserFastPaths.h"
 
 #include "core/StylePropertyShorthand.h"
 #include "core/css/CSSFunctionValue.h"
 #include "core/css/CSSValuePool.h"
@@ skipping 91 matching lines @@
 
     if (string.is8Bit()) {
         if (!parseSimpleLength(string.characters8(), length, unit, number))
             return nullptr;
     } else {
         if (!parseSimpleLength(string.characters16(), length, unit, number))
             return nullptr;
     }
 
     if (unit == CSSPrimitiveValue::UnitType::Number) {
-        bool quirksMode = isQuirksModeBehavior(cssParserMode);
-        bool svgMode = cssParserMode == SVGAttributeMode;
-        if (number && (!quirksMode && !svgMode))
+        if (cssParserMode == SVGAttributeMode)
+            unit = CSSPrimitiveValue::UnitType::UserUnits;
+        else if (!number)
+            unit = CSSPrimitiveValue::UnitType::Pixels;
+        else
             return nullptr;
-        if (svgMode)
-            unit = CSSPrimitiveValue::UnitType::UserUnits;
-        else
-            unit = CSSPrimitiveValue::UnitType::Pixels;
     }
+
     if (number < 0 && !acceptsNegativeNumbers)
         return nullptr;
 
     return cssValuePool().createValue(number, unit);
 }
 
 static inline bool isColorPropertyID(CSSPropertyID propertyId)
 {
     switch (propertyId) {
     case CSSPropertyColor:
@@ skipping 898 matching lines @@
     if (isColorPropertyID(propertyID))
         return parseColor(string, parserMode);
     if (RefPtrWillBeRawPtr<CSSValue> keyword = parseKeywordValue(propertyID, string))
         return keyword.release();
     if (RefPtrWillBeRawPtr<CSSValue> transform = parseSimpleTransform(propertyID, string))
         return transform.release();
     return nullptr;
 }
 
 } // namespace blink